The Nintendo Wii was never really about power. When it launched in 2006, Microsoft and Sony were busy flexing with the Xbox 360 and PS3, pushing HD graphics and raw horsepower. Nintendo went the other way entirely: a modest little white box that ran at 729MHz, with 88MB of RAM, specs that even at the time looked humble.
What it had instead was motion controls, a genius price point, and your grandma genuinely wanting to play it at Christmas. All of which makes it a pretty unlikely candidate for running a desktop operating system. And yet...
Developer Bryan Keller recently got Mac OS X 10.0 Cheetah (Apple's very first OS X release, from 2001) actually booting on a Wii. Not emulated. Running on the hardware itself. The reason he thought it might even be worth trying is that the Wii uses a PowerPC 750CL processor, a newer relative of the same chip family Apple used in the old G3 iMacs and iBooks. Basically, the same DNA, but different generation.
Getting there was anything but simple. He wrote a custom bootloader, patched the OS X kernel, built drivers so the system could read from the Wii's SD card, fixed a colour mismatch between the Wii's video output and OS X's graphics code, and hunted down 25-year-old USB driver source code on IRC just to get a keyboard and mouse working.
He was so deep into it that he packed the Wii in his luggage and took it to Hawaii on holiday, he says. The result: a fully bootable Mac OS X install on a Nintendo Wii, with a working keyboard and mouse. He also shared a full walkthrough on his blog, and if you're feeling brave, the source code is up on GitHub.