Originally Posted By: sein
Also, formatting a disk on a PowerPC Mac will make it unbootable on an Intel Mac so be careful with that.

I thought the same thing, but it appears this might only apply to internal drives. I can put my PowerPC Mini into firewire target disk mode, and then boot the drive inside the Mini on my Intel MacBook Pro. This is with 10.5, I know it won't work on any previous version since the kernel wasn't universal prior to Leopard.