Installing Mac OS X on a Flash Drive

[ARH]

Since we've had a 2GB Kingston SD card and a card reader at hand, we decided to use those in this experiment. But you can naturally use other USB dongles, memory cards, and external hard drives. For installation we used an Intel-based Mac machine, because we did not have an old PowerPC at hand (besides, it would be harder to install with the latter). And don't forget that you won't be able to run an Intel system on a PowerPC and vice versa.

http://www.digit-life.com/articles2/td/mac-flash.html