JayCut is a free, online video editor. You can upload your own video (and image) files and optionally add transitions, text and audio. Once you are finished working on your video project, you can download or publish it in a variety of ways and formats (e.g. .flv, .mp4 or .avi).
This is a great tool for students that don’t have access to proprietary, video-editing software like iMovie or FinalCut Pro.
Check it out here: http://jaycut.com/.