I love cover songs. This probably dates back to my highschool "emo" phase when I was obsessed with "Punk Goes Pop" for some strange reason.
A cover song is truly great when it takes a song you know already and just completely flips it around. So here's ten of my favorites. I haven't included any of the amazing covers (Buckley, Wainright, JT) or Leonard Cohen's "Hallelujah" because they could probably fill up a blog post of their own. Also, I didn't consider songs first made famous as a "cover" (e.g. Hendrix performing Dylan's "All Along the Watchtower").
In no particular order:
(couldn't find a video)
Ben Lee: MGMT's "Kids"
Bright Eyes: Elliott Smith's "The Biggest Lie"
The Gaslight Anthem: Kelly Clarkson's "I do not Hook Up"
Wilco: Daniel Johnston's "True Love Will Find You in the End"
Magnolia Electric Company: Warren Zevon's "Lawyers, Guns, and Money"
(mainly because I love this song, and not because it's a particularly novel take on it)
Matt the Electrician: Journey's "Faithfully"
(embedding was disabled, but this is by far the best version)
Stevie Wonder: The Beatles' "We Can Work it Out"
And finally, a personal favorite-
Steve Carell & Dane Cook: Pete Townshend's "Let My Love Open the Door"