Check out jumpcut.com
It’s a completely free movie making site. It’s basically a cut down version of iMovie online. The real benefit to this site over using iMovie or windows movie maker is the fact that it is so simple to use. Plus the fact that you can save your work online and come back to it anytime from any PC.
You can also import photos from facebook and Flickr which makes this a great tool for editing your videos taken with your phone or camera to put on YouTube or your own site / blog.