I couldn't resist taking a look at the "iSnow Portable" project. OS X 10.6.2 on a usb flash drive, bootable on most PCs. Works surprisingly well. I suppose if you install it using a macintosh, (which you do) and then take the flash drive to a pc and boot it, you're not violating at least one of the usual silly licensing agreements, eh? It says you can't
install it on a non apple brand computer, but doesn't say anything about
running it.
Everyone knows if you take a live CD or a flash drive with firefox to another computer, you're not
installing anything.
I personally just use it to demo to PC users what Mac OS X looks like. Heck, the way I see it, I'm drumming up Apple some business.