I loaded MintPPC 11 (linux for powerpc computers) on my TiBook. So far it is awesome. I didn't even have to mess with my "macwireless" pcmcia wireless card. I put in the name and password and bam was online. No additional drivers. I will try loading it on my original ibook and 333mhz tray loader imac this weekend.
Check it out: mintppc.org