I use a new MacBook Pro 13" every day but started up my trusty old Powerbook G4 this morning to find an old email address and a black line appeared across the screen about a third of the way down. What causes this? Restarted but didn't go away. The Powerbook is now about 8 years old, tediously slow but has always been amazingly reliable. Does this tell me the end is nigh? Can't seem to find any threads that relate to this problem.