There are a ton of projects that have used the Raspberry Pi, BeagleBone, and Arduino boards for gaming emulation, even in the form of handheld and tabletop systems. While they may be a dime a dozen, they are no less fun to build, especially if you are into retro gaming. Rossumur's ESP_8_Bit is a minimalistic approach to retro 8-bit gaming and allows users to emulate three popular consoles, including the NES, Atari, and Sega Master System, complete with ROM selection menus.
The ESP_8_Bit also enables users to use nearly any HID-compliant controller, as long as they are Bluetooth Classic or IR compatible, which includes the WiiMote, Atari Flashback 4, or even Apple TV remotes. The platform also supports PAL/NTSC color composite video outputs, so all users have to do is connect it to their TVs, and it's ready to play. That said, Rossumur points out that going the NTSC route requires a stable high-speed reference clock, as the system tends to get finicky.
The ESP_8_Bit emulator was designed around the ESP32 microcontroller, which is the only piece of hardware used for the system, and nothing else is needed beyond a micro USB cable and whatever compatible controller users may have on hand.
Rossumur also notes that the ESP32 also includes an ultra-low-noise fractional-N PLL, which can be tuned to produce DAC sample rates up to 20MHz. While its intended use is to synchronize audio sources running at different frequencies, it can also be used to create accurate color carriers. Rossumur has a detailed walkthrough of his ESP_8_Bit game emulator on his website, complete with schematics and the code needed to get up and running, for those interested in recreating his build.