Yesterday my computer had been running for 5 days straight and when I looked at the Activity Monitor under "Active" it read 957mb. I wasn't running any apps at the time and was wondering if there was a reason for this? Maybe it's because I hadn't restarted in 5 days? I also hadn't slept the computer in about 3 days as I'd been downloading quite a lot. I turned it off before I went to bed and everything's fine today, but I'd like to know what caused memory usage to be so high. I should have taken a screenshot of the activity monitor, but I didn't. I have 2gigs of memory so the computer using so much memory wasn't a problem, but I'm just curious. If anyone can explain, then that'd be nice.