Friend's Phoebe Buffay (Lisa Kudrow) has a long list of occupations during the course of the show, including singer-songwriter for which she is best known for her least popular song, "Smelly Cat". Encouraged by a record producer, she records the song professionally as both a track and a music video, but her voice for both is overdubbed by another artist, E.G. Daily, who is less attractive but a much better singer. However Phoebe still appears in the video, along with three backing vocalists, a cast of homeless people, and a possessed (did you see its eyes?) cat.
Read the stories behind ten such videos (and watch them) in this list at brainwavez. Link -Thanks, Mandy!
http://www.youtube.com/watch?v=D3rNBAMt-kg