Bohemian Rhapsody in Wayne's World comes to mind. And that's all I can think of. There's got to be more! The Throbbing Brain needs to weigh in. And while I have never seen Glee or High School Musical, musicals and their ilk are immediately disqualified. Unless a most excellent argument can be put forth that argues otherwise. But don't get mental. Party on!
1) What is a lip dub? See: http://en.wikipedia.org/wiki/Lip_dub
2) Are lip dubs fun? Yes!