First off, I'm running 10.3.3 with all the most recent software updates. I've actually been having this problem over the past 2 or 3 weeks: my PB will freeze randomly once a day or so and force me to hit the power button. No kernel panics or error messages of any sort... my desktop will simply freeze. The mouse cursor is usually responsive for a few seconds before it, too, freezes on me. The only constant I've noticed throughout these random lockups is that I'm running iTunes, although this may just be because I'm constantly running iTunes. When I experience these lockups, the current song in iTunes will usually continue to play for a little while, and then cut in and out intermittently until it stops altogether. I'm running iTunes 4.5 now, but I was still having problems prior to the new version. Rebuilding the iTunes.plist file doesn't seem to have any effect. I've tried to isolate the problem by switching apps on and off (Synergy, Quicksilver, and iChatStatus to name a few), but the problem remains. I've run the Disk Repair utility (booting off the Panther CD) as well repaired the disk permissions. I've also run the Extended Test on the Apple Hardware Test, which passed without a hitch. I'm going to try resetting the PMU and then swapping out my RAM, but beyond that, I'm kind of running out of options. I'd like to avoid reinstalling the OS if at all possible. Funny thing is I have a friend who just bought a new 12" PB (1.33), and he's having the exact same problem. Anyhow, I'm at a bit of a loss, so I was curious if anyone else here had been experiencing the same problem. Thanks.