Best Covers

@garebear +1 on Gregg Allman's version of "These Days," although I've always liked the original version by Jackson Browne just as much. However, I think the ultimate version is when Gregg and Jackson perform it together live at the "All My Friends" tribute concert for Gregg. 

I heard that the only performers at that show who knew that Gregg was terminally ill were Jackson Browne and Don Was; thus, making that performance even more poignant.

In the "hilarious" category:

"Jump" - Aztec Camera

"I Will Survive" - Cake

"Pump It Up" - Prozak For Lovers

In the "Wow, that took courage and talent to tackle that one:"

"Walk On the Wild Side" - Edie Brickell & New Bohemians

"River" - Rosanne Cash (Joni Mitchell)

"Just a Little Lovin" - Shelby Lynne [an entire album of songs done by Dusty Springfield] 

"Chelsea Hotel" - Lloyd Cole

"Everybody Knows" - Concrete Blonde

"All Tomorrow's Parties" - Bryan Ferry

"If I Were a Carpenter" - Bob Seger

^^^^^^^^

Technically speaking, no; but, that's based on a black & white and/or narrowed minded perspective. I agree that a good remix often feels like a complete reinvention of a song; and, many previous examples cited in this thread fall into that category ("Sweet Jane" - Cowboy Junkies). So, be a "rule breaker" and see what kind of reaction that you get. Who knows, it might extend the life of this thread, albeit in a slightly different direction.