9. 'Xanadu'
Directed by Robert Greenwald
Starring: Olivia Newton-John, Gene Kelly, Michael Beck

This was the movie that essentially created the Golden Raspberry Awards, awarded annually to the worst movies in any given year. Xanadu was so bad that people wanted to remember how bad it was. And Gene Kelly is in it! The insane story is about a Muse of Olympus named Kira (Newton-John) who convinces her old flame and new flame to team up and create a disco for her. It's a relic from a forgotten age that disco historians remember fondly.