The Sega Mega Drive—or Genesis, if you're in the US—remains the company's most commercially successful home console, and is famous for going toe-to-toe with Nintendo during the early '90s console wars.
It's also a system which, in recent times, has seen an inordinate amount of homebrew development, with multiple new games arriving on a yearly basis.
Another cool new development regarding the console is the fact that it Fusix, a UNIX-style operating system, has been ported to the machine, which opens up several interesting possibilities in the future (thanks, Hackaday).
Consoles like the Mega Drive and SNES usually run code booted from cartridges, and that's about it—but with a functional OS, the Genesis is potentially capable of behaving more like a modern-day computer.
It offers a working shell and the typical UNIX utilities, but as noted by Hackaday, the 64k of memory offered by the console is going to limit things a little.
Still, it's amazing to see so much effort being committed to doing cool stuff on ageing hardware.