Also see this thread: http://forum.dvdtalk.com/music-talk/...re-covers.html

Rod Stewart "That's What Friends Are For" (predates the Dionne & Friends version by 4 years)
http://www.youtube.com/watch?v=jSkqVVljCEc (The attached video is bizarre... the song was in Night Shift, not Sleepers)

Crescent City Blues by Beverly Maher and the Gordon Jenkins band. Not exactly a cover, since Johnny Cash changed most (but not all) the words and kept the tune when he turned it into Folsom Prison Blues.
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Stupid video but the only one I could find with the whole song.

"Alabama Song" by Kurt Weill & Bertolt Brecht

(This is an faithful recording of the original song by Lotte Lenya, who sang the song in the original stage performance of its play, even though this particular recording was decades after the song was written):
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Heck, this song was actually written before Jim Morrison was even born!

Wow, interesting to learn that this song was an import from Grace Slick's previous band. And, looking around at other videos, "White Rabbit" was another song Grace Slick did an earlier version with The Great Society before importing the song over with her when she joined Jefferson Airplane:

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(Note that it takes about 4.5 minutes in this version before the lyrics show up)
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