I had Limewire years ago and my hard drive developed som extant allocation errors (I can't remember exactly what they're called now -- essentially I believe it was problems with data trying to occupy the same space on the drive). It required Disk Warrior to fix; disk utility could not touch it. I can't say for certain that it wouldn't have happened anyway. I just remember reading on one of the Apple support boards covering this topic (it was hard to find, too) that Limewire was a suggested cause. How that happens, I don't know. I took Limewire off -- had my own struggles with my conscience and my conscience won -- and have not had a reoccurrence. I have a PC friend who uses Limewire (her kids do, anyway) and they have had many, many, many woes with their computer. I keep telling them to remove Limewire...