I used to have an old Powerbook before I upgraded to a MacBook and this problem happened to me continuously. My power adaptor was constantly fraying to the point where I had to buy a new one every 3 months. This hack shows you how to repair your old adapter to stop this from happening forever. Plus you get to see what’s really inside those over-designed white cubes.
Repairing a Powerbook G4 45x AC Adapter – Link