If you have the nostalgia itch and know how to use a soldering iron and a Dremel, you can basically make an infinitely better version of this yourself with a Raspberry Pi.
Here is a video of a guy who put one in an old NES case:
I've also seen them built into old GameBoys and even old NES game cartridges. There are a ton of guides online that can walk you through it step by step. Last winter, I built one into a non-functional NES that I got off eBay for 19 bucks (didn't have the heart to gut a working NES). Gave it a new paintjob with a cool Mega Man logo and loaded it up with about 1,600 games (...that I...found...in the forest...), including pretty much every NES and SNES game ever made, as well as a bunch of GBA and PS1 games. Definitely worth it.