If you need to make an important life decision, you likely reason it out and try to come up with the optimum path for yourself. On the other hand, if a decision isn’t that important or there are two seemingly equal options — like where to go for dinner or what movie to watch — a flip of a coin will suffice. Hacker “lonesolesurfer” wasn’t content with using monetary disks to make his choices, and instead came up with this electronic version.
This device uses a 555 timer along with resistors and a capacitor to determine answers, displayed on a green (yes) or red (no) LED. A mercury switch activates the circuit, so once the double-CR2032 battery pack is turned on, you tilt the device in order to get an answer to your query. It’s a great example of what can be done with only discreet components, and a neat experiment if you want to get started with 555 timers.
It is noted in the explanation video below that lonesolesurfer also made a version with an outer shell constructed out of a dental floss box. They’re a nice size for small projects, and he mentions that they conveniently come apart easily.