"Weird Al" Yankovic has included backwards messages in two of his songs:

1.) On the album, "In 3-D", a little over halfway through the song, "Nature Trail To Hell", there is a short non-vocal musical score. If you listen very carefully, you can hear Al say, in a very evil voice, "Satan eats cheese whiz" backwards.

2.) On "Bad Hair Day", near the end of "I Remember Larry" where Al repeatedly sings "Yes, I remember, remember, remember...", if you listen closely you can catch another backwards message that says, "Wow, you must really have a lot of free time on your hands"