The Best of Open Sauce 2025: Our Top 9 Picks

Open Sauce 2025 just wrapped and if you weren’t lucky enough to make it out to the Bay Area for the convention, you missed out. Even if you were there, you may have missed something awesome — there was a lot to see, after all.

There were, of course, booths that nobody could miss, like those from Elegoo, Makera, and Crunch Labs. But Open Sauce is for makers and created by makers, so we were on the hunt for the kinds of smaller exhibitors that embody the Hackster spirit.

That’s why we scoured the conference halls and braved the pleasant 70° outdoor weather to find the most impressive, most innovative, and most bizarre projects of the event. These are our picks for the nine exhibits that best displayed those traits.

#9 – Tic-tac-toe with a twist

This one was easy to miss, because it looks like a simple electronic version of tic-tac-toe at first glance. Any elementary school student can tell you that tic-tac-toe is a terrible game, as it always ends in a draw if both players have even the smallest amount of experience with the strategy — so much so that even using the word “strategy” feels silly.

But what if you tweak the rules a bit? What if, for example, only the player’s three most recent marks remain on the board? Or, how about if the marks “fall down” to the bottom-most available space on the board, like Connect Four?

That’s exactly what Dorian Todd of Full Contact Engineering achieved with his electronic tic-tac-toe board and it changes the game dramatically, introducing genuine strategy. In every game we played, Dorian soundly trounced me as I struggled to wrap my brain around the new mechanics. And if a human opponent isn’t available, Dorian also included an AI to play against — though you probably won’t beat it, either.

#8 – A CNC router... that you move manually?

Conventional CNC machines, like mills and routers, need to be larger than the material they work with. That’s because they need motion systems that can move the tool to any part of that material. The result is big and expensive machines that few makers can accommodate or afford. But the Compass CNC V1 is anything but conventional and its designer, Cameron Chaney, implemented a very clever workaround: replacing most of the motion system with the operator’s own body.

The Compass CNC V1 is a bit like a handheld router and isn’t much bigger than one. The operator moves it across the surface of the material to make cuts as a small display guides them along the programmed toolpaths.

But here’s the ingenious part: the machine has a miniature motion system of its own to perform small movements (about 20mm) and correct for errors in the operator’s motion.

The operator just has to move the Compass CNC V1 pretty close to the toolpath, using the on-screen guide, and the machine will perform the fine adjustments to maintain accuracy. Owners can cut material and parts of any size (include 4x8 sheets and larger), using a machine that is affordable and doesn’t take up much shop space.

Compass is currently accepting pre-orders for kits that will ship in October 2025. Those kits cost $790 and include all of the “vitamins,” such as the Teensy 4.1 used for control and the stepper motors. Owners can then 3D-print their own frame and assemble a Compass CNC V1 using the handheld router or spindle of their choice.

#7 – Goldfish can drive cars now

When fish emerged from Earth’s primordial oceans on their quest to evolve into pandas, humans, and armadillos, they did so on legs (or leg-like appendages, at least). However, evolution is a very slow process and today’s goldfish don’t have that kind of time. So, Laura Caroline Jung, Phoebe Lin, and Ria Mirchandani built the Fishmobile to give goldfish access to land without the wait.

Surprisingly, they aren’t the first to do this. A team from Ben-Gurion University built something similar a few years ago and that was the inspiration for the Fishmobile.

The Fishmobile is an Arduino-controlled robot that drives around on Mecanum wheels while carrying a fish tank. Some ultrasonic sensors help to avoid collisions, but the robot will ultimately be piloted by a goldfish. The goldfish will direct the vehicle by swimming around in the tank, which a Raspberry Pi will detect through a camera.

That hasn’t quite come to fruition yet and the demonstration at Open Sauce wasn’t really being controlled by a fish. In fact, the “fish” in the tank was a robotic imposter. But it is only a matter of time until the Fishmobile gives goldfish the independence they crave.

#6 – Acrobatics 100

Your typical wizard is going to be dumping everything into stats like intelligence and wisdom, which leaves them woefully unprepared for acrobatic feats. So, what is a magic-wielder to do when they need to traverse a chasm on floating stepping stones? Tech Wizard’s solution was to cast self-leveling by building a bag of holding balance.

This backpack works using the same principles as self-balancing robots and inverted pendulums, by rotating mass and using the moment of inertia to provide an opposing, counteractive force to tipping. In this case, the mass is a weighty flywheel and a CubeMars actuator spins that under the control of a Teensy development board.

That entire contraption fits inside a large transparent cube with shoulder straps. When worn securely upon one’s person, it will work to stay upright and will therefore keep the wearer from falling over. The effect is unnatural, almost magical balancing ability that would usually be reserved for rogues and rangers.

#5 – Milling metal with minimal money

Machine tools are notoriously and frustratingly expensive, which tends to put them out of the reach of most makers. As mentioned in the Compass CNC section, they need to be larger than the material they work with. And it becomes even trickier when working with metals and especially with harder and tougher metals like tool steel, which require extreme rigidity.

But the Shariff DMC2 Mini CNC mill manages to be affordable and compact. And, based on what we saw at Open Sauce, it sure seems capable. Best of all, it costs just $2,500 in kit form (which buyers can assemble themselves).

Despite that low price, it has pretty impressive specs. It runs on single phase 120V power (or 220V in applicable countries), has a 12×7×5.5” work envelope, a 2.2kw (3HP) spindle at 24000 RPM with an ER20 collet, closed-loop steppers acting as servos, a central lubrication system with hand pump, a flood coolant system with chip tray and filtration, a full enclosure, and it runs a Mach3 controller.

The samples we saw at Open Sauce looked great and included common materials like brass, aluminum, and steel, along with tougher materials like titanium and T2 tool steel.

This is all very promising and we’re going to do our best to get a DMC2 Mini to review for The Maker’s Toolbox. The kits are currently in stock, but assembled machines are out of stock. Shariff DMC told us that they’re focusing on producing kits, as those are more popular and much more affordable.

#4 – The origin of a cargo cult

Most Open Sauce attendees didn’t get to see it, but on Thursday the San Mateo County Event Center was buzzing with activity as exhibitors rushed to get their booths set up. Keith Sachs saw the same thing at Open Sauce 2024 and so he came prepared this year with a very practical cargo robot.

It is a bit like a robotic mule, which Sachs designed to lug around boxes and equipment. Its frame is made of interlocking aluminum panels fabricated by SendCutSend, which collapse down into a package small enough to fit into a carry-on Pelican case for transportation. It is driven by a hacked hoverboard and Sachs can control the bot’s movement through a standard RC transmitter and receiver set, with power coming from Hercules (Harbor Freight) power tool batteries — the only parts of the robot that can’t go in the carry-on case.

This robot has undeniable utility, but it turned out to also be a big hit as a makeshift vehicle. It can easily carry the weight of one or even two people, and both William Osman and Engineezy were spotted taking the it for a spin.

Sachs plans to improve the design for next year’s Open Sauce, so be sure to keep an eye out for that. And consider bringing some cash, so you can bribe Sachs into helping you move boxes to your own booth.

#3 – The keyboard of a thousand keys

How many unique words do you use on a regular basis? Estimates vary dramatically, but it is safe to say that most English speakers can get by in daily conversation with just a few thousand. If you’re willing to limit your diction, you could probably even stick to only the thousand most common words without too much trouble.

Attoparsec put all one-thousand of those words on a single massive keyboard, each on its own individual key.

Yes, that means there are one-thousand keys. No, this is not practical. Yes, it is very cool.

That wasn’t quite as simple as just putting together 9.615 keyboards, as Attoparsec wanted it work like a “normal” keyboard and that meant using a single microcontroller. But even the most efficient possible keyboard matrix would require 64 I/O pins — far more than the typical microcontroller has to offer. Fortunately, GPIO expanders exist and they let Attoparsec get to all of the necessary columns and rows with a Teensy 4.0 development board. It is like a pyramid scheme keyboard matrix.

But as you probably guessed, nobody sells full sets of key caps with English’s top one-thousand words and so Attoparsec needed to make his own. For a previous project, he resin-printed his own key caps. However, that is a very time-consuming process that wouldn’t make sense for a keyboard of this scale. Instead, Attoparsec used dye sublimation to print the legends on blank key caps.

Typing on this keyboard is inefficient, to say the least. And typing at high speed would require arm muscle endurance beyond what most of us possess. But at least you’d never have to worry about typos.

#2 – Hollywood’s prop secrets

When you watch a Hollywood blockbuster — or even an indie genre film — the true nature of the special effects are hidden from you as a viewer. The purpose of a movie is to immerse the audience in a story and it would be counterproductive for props or special effects to steal the show.

However, many of us take a special interest in those props and effects, which is why Davis DeWitt set up his exhibit to provide a look into the magic that happens behind the scenes. DeWitt has a great deal of Hollywood experience as a prop maker, special effects engineer, and filmmaker. He has worked behind cameras on movie sets and built props for the other side of those cameras, giving him unique insight into a famously enigmatic industry.

The star of DeWitt’s booth is actually a movie star himself, called Newt. You can see Newt on the silver screen for yourself in The Lightning Code as the plucky robotic sidekick. Calling Newt adorable would be an understatement and he was a big hit at Open Sauce. He isn’t an inert special effects placeholder either — he’s a fully functional robot that DeWitt piloted throughout filming.

DeWitt also showed off another movie prop: a remote-controlled smoke grenade that rolls perfectly into frame to achieve the ideal shot.

On top of that, DeWitt set up a focus-pulling demonstration with the help of Forrest Gibson, a cinematographer and first AC on numerous productions. Attendees got to try pulling focus on a moving subject, learning for themselves just how tricky the job can be and how impressive it is that we never even notice it as viewers.

Finally, DeWitt’s own personal projects garnered a lot of attention from everyone passing by — including Allen Pan. One of those projects is a Condiment Cannon that flings single-serve packets of jam. Another is a handheld PEZ candy-launcher that hurls the sugar bricks at high velocity.

DeWitt has a rapidly growing YouTube channel with the kind of high production value you would expect from someone with his background, so be sure to check that out.

#1 – Fleshy fun

Have you ever looked into the eye of a vintage Polaroid camera and seen it looking back at you? Have you ever stuck your finger into the mouth of an old Hewlett-Packard so it could get a taste for you and tell you its thoughts?

You could have done both of those very weird things if you had visited The Flesh Emporium exhibit at Open Sauce.

The Flesh Emporium is a peek into the mind of Ethan Calfee, whose creations are like H.R. Geiger-esque amalgamations of organs and vintage tech.

One project, the Eyeball Instant Camera, started its life as an innocuous Polaroid 420 Land instant camera. But if you peer into its lens, you’ll find a grotesque eye leering back at you from the camera’s bellows. If you let the camera snap a shot of you, a thermal printer will spit out the photo with potentially dire predictive imagery.

Calfee’s vintage Hewlett-Packard PC is even more delightfully disturbing. The growths will certainly catch your attention — they cover the chassis like oozing tumors. One of those on the front is actually an orifice that Calfee charitably called a “mouth.”

If you stick your finger in there and start feeling around the top, you’ll touch some kind of firm protrusion. And yes, the experience is exactly as suggestive as it sounds. When you make that contact and the computer gets a taste, it will form an opinion of you. And it isn’t afraid to share its thoughts by printing a card and excreting that from its floppy drive.

It didn’t think very highly of me at all and that hurt. But others received more favorable evaluations and I feel a compulsion to trust the machine’s judgment.

More importantly, The Flesh Emporium encapsulates what people love about Open Sauce and the maker community as a whole. It is raw creativity for creativity’s sake and a reflection of the creator’s own unique personality, which is what we attended the event to explore.