i was watching some clips of X Factor and the whitney houston cover of I will always love you was being covered and i've heard other artists cover her version of the song and it got me to thinking.....

what are some other cover versions of cover versions

I fought the law was originally by the crickets sans buddy holly, and then the bobby fuller four covered it, and then later the clash covered the bobby fuller four version.

Everybody Needs Somebody To Love was originally Solomon Burke, soon covered by Wilson pickett, then pickett's faster version was covered by the Rolling Stones and later the Blues Brothers.

Whole Lotta Love by Led Zeppelin was heavily based on "You need Lovin" by the Small Faces, which itself was a modified version of "You Need Love" by Muddy Waters.

Led Zeppelin's Babe I'm gonna leave you was originally by Anne Bredon, but it had been previously covered by Joan Baez which was probably where they heard it from

House of the Rising sun by the Animals was performed on Bob Dylan's debut self-titled album, but the song was originally a traditional blues/folk song.

The Clash song Wrong Em Boyo was a cover of a song by the rocksteady group The Rulers, whose opening passage is a quotation of the song Stack A Lee (also rendered Stagger Lee Stag o'lee, etc. etc.) another old folk song performed by numerous other people since the 1890s including Mississippi John Hurt, Archibald, Lloyd Price etc.

The Who's hard-rocking baby don't you do it which was a bonus track on the reissue of Who's Next was originally performed by Marvin Gaye, and had also been covered by Stevie Wonder shortly after the original Marvin gaye version.

Cream's Sunshine of your love was inspired by Jimi Hendrix, who was himself heavily influenced by Cream. There have been a few cover versions based on the faster live cover that Hendrix performed as a tribute to Cream.
[Edited 11/16/07 20:51pm]