Running Snow Leopard on a Late 2007 MacBook, and I booted it up today to see that I had 15 GB left (normal). 4 hours later, I get an alert that I'm running low on Hard Disk space, so I open a new Finder window to see how much space I have. It tells me 10 MB. After 5 minutes, this dropped down to 0 KB, and all of my applications opened "paused", and I had to force quit them. I don't have 0 KB left, I have 15 GB, but Finder isn't telling me that. Is there any way I can fix this?