This time it isn't Linux running on your ipod -- it's Linux running off of your ipod. Load up the files and no matter how boned your PC becomes, you can boot into a version of Linux, complete with GUI, restore utilities and other goodies.

Sounds pretty neat, but it's actually somewhat more pointless than it sounds. Not all PCs can boot from USB devices yet, for one thing. For another, there are already plenty of Linux "live CDs" available: pop em in your CDROM drive, power up, and try out a new operating system -- all without installing a thing. Less sexy, I guess, but more practical. Have a look at Knoppix if you're feeling curious; if you're feeling mischievous, have a look at PHLAK.