AppleCare Rocks
system
So, last week my powerbook was dying with some sort of trackpad temperature sensor malfunction. Sent it in on Thursday to AppleCare overnight in a box they sent me overnight the day before. By the end of the day Friday they had replaced the top case and shipped it back... it got here today. So far, no problems. Lesson: if your problem is well-diagnosed, try to have AppleCare send you a box on Monday. You'll have your computer back by Thursday.
I was able to borrow someone's old powerbook and boot off of a cloned external drive. When the computer got back today, I cloned the external back to the powerbook using SuperDuper's SmartUpdate feature (that only copies the differences to result in an exact copy). I lost less productivity this way.