I hereby declare this weekend Student Backup Weekend for Spring Semester! And while I'm declaring it, I'll declare that Student Backup Weekend isn't just for students anymore.
You haven't backed up your work. I know you haven't. So, this is the weekend to do it. The semester's about to get real, and ugly. You're thinking that you'll back up after your projects are done, maybe after finals.
It's too late then. When a failure happens, it's going to happen in the next couple weeks, i.e. the worst possible time. If you back up now, you'll be able to recover in case of disaster. If you don't, you're going to be screwed.
Get another hard drive or USB stick, and make a copy of all your documents, and ideally your media as well. If you can't get one, use a lot of DVD-r's. Then, get a free Dropbox account, and put your most critical documents there (get friends to sign up and get yourself some extra space. I'd do this myself, but I'm maxed out already). Encrypt your backups if you're twitchy.
Go do it. Now. I'm advising you based on personal experience, and also based on patterns I've seen with students. There's nothing sadder than a semester long film completely lost right before it is completed.