Songs That Should Never Be Sung

And now for a little fun. Have you ever heard a song that just should not have been performed by the musician or group who recorded it? In your opinion, what song should never be sung by what artist? They don't ever have to have been actually recorded. Here are a few of mine to get you started. Put yours in the comments.

"Silent Night" by Metallica
"Old Man River" by John Denver
"We Will Rock You" by Enya
the Mormon Tabernacle Choir sings "Duke of Earl"