Those of you who have a 2nd generation 12" powerbook, I wan't you to do the insane!
Save everything important.
Close your powerbook.
Unplug powerbook.
Take battery out.
Note whether or not the sleep light is pulsing.
Plug back in and put battery back in.
Post results.

Why? Cause while I was using my mother's 15" powerbook it crashed, force restart didn't work, I unplugged it and took the battery out, it was still asleep.

I think it's obvious what the problem is here.
Clearly, your powerbook, through an always on connection to the internet, has accrued so much knowledge that it has acheived sentience and learned to draw power from the ambient heat in the air.

But seriously, the powerbooks and ibooks have a reserve battery to power the clock circuit. I guess it draws on that reserve to keep it asleep when it has to.

I'll check on this here 900 mhz g3 iBook.

Yup, big no from the pre g4 iBook department.

The clock battery is far from big enough to keep the computer running on asleep for too long.