We have a working Apple iBook, 14.1" screen. Debian 6.0 saves the day!
The stats, I think, are: 256 or 384 MB RAM, ATI graphics card, 30GB hard drive, 700 mhz G3 PPC processor
-xorg, fluxbox, thunar
-Iceweasel, though only a few tabs at a time and even then it takes a bit (installed NoScript, Adblock, Flashblock and Ghostery to help keep memory down)
-keyboard and mouse, usb mice
-Marathon/Aleph One in software rendering mode (runs fairly well actually)
-Ur Quan Masters
What dosn't work:
-wi-fi (which would be WEP if it worked anyway, so who cares)
-changing xorg to a 16 bit color mode to get more video RAM for 3D acceleration
What will burn the hair off of your skin:
-the heat of the night
What will give you a back ache:
-the thing is darn heavy, mister, are you sure you're on the fifteenth floor?
They don't make laptops like they used to. You could kill a man with this thing. I'm not saying you couldn't with any other laptop, but it involves less whacking and a smaller time commitment.
I'm pretty pleased with it though. A friend mostly gave up on the poor lad and now look at 'em. He's as useful as any other laptop, save the sound and wi-fi. But who needs those things anyway.
I was tempted to try and install OSX on there to compare performance. The PPC iBooks were apparently supported up to 10.4. I wonder if a friend has an install disc.