Hey- I'm running Compressor 2 for long periods of time on my Powerbook (Aluminum 1.25 GHz G4 w/ Tiger). Running 2-pass DVD encoding on about 90 minutes of video. Needless to say it's an all-night affair. When I'm running Compressor, the screen saver won't come on and the display nevers goes to sleep. Obviously, I can use a hot corner to activate the screen saver, but the display never powers down. The display will turn off when other apps are running long processes, but not Compressor. Any ideas? Also, are there any risks to running these really long, processor-intensive compression jobs on a Powerbook?