Pseudo Echo’s version of the Lipps Inc song Funkytown.
I know there’s a ton of folks who hate the 80’s synthesizers, but I was a teen in the 80’s so that worked for me. The lads from Pseudo Echo just seemed to be having so much *fun *with it, that’s what hooks me in far more than the original.
Another Johnny Cash cover, “Ring of Fire” was originally sung by Anita Carter (his future sister-in-law, incidentally)
I’m a big fan of the Vanessa Carlton cover of “Paint it Black” by the Rolling Stones
I’ve loved the Indigo Girls since I saw them in concert back in 1989 but I gotta go with DS on Romeo.
Agreed!
I would add Steve Earle’s version of “Dead Flowers” which I think is grittier and sadder than the Stone’s. Same with Earle’s version of Springsteen’s “State Trooper”, although I only heard the Springsteen version once.
The Kinks did “You Really Got Me”.
Then, Van Halen did it.
Anyone who thinks the original is better hates Jesus, America, and Cameros.
I like Metallica’s “Loverman” better than the Nick Cave original.
Alison Krauss and Union Station: Baby, Now That I’ve Found You beats the Foundations’ version.
And the Monkees’ version of I’m A Believer outshines Neil Diamond’s
I was originally hesitant about posting my suggestion for fear of being labelled a blasphemer, but after some of the suggestions I’ve seen so far, I don’t think I have anything to worry about.
Here goes:
My vote is for You’ve lost That Lovin’ Feeling by Hall & Oates The original has bored the crap out of me ever since I was a kid. The cover makes me want to sing alaong.
That’s a cover song? I was about to say that my favorite cover of “Ring of Fire” is sung by Social Distortion. It just sounds so intense to me, more so than Johnny Cash’s version (not to disrespect the Man in Black, of course). So basically I’ve been rocking out to a cover of a cover. 
I love the way Mike Ness shouts “Let it burn!” right before the guitar solo.
I also prefer Fine Young Cannibals’ version of “Ever Fallen in Love” to the Buzzcocks’, probably 'cause I heard it first.
Thus proving Threadkiller’s assertion. There is just no way you heard Supertramps version before the Goo Goo Dolls version.
I would make a slight addition to Threadkiller’s observation.
The first one you hear sounds right if an only if you actually liked it too.
Some band butchered Video Killed the Radio Star in a movie soundtrack can’t remember who) and someone in my family somehow managed to never hear the original Buggles version. They heard the “soundtrack” cover and loved it. It became their “first” version. When they heard the Buggles version they went “meh”.
To rephrase: if you hear a song for the first time and really love it, then no other version (whether it predates or postdates your version) will be as well liked by you.
I just remembered another one.
The Tea Party’s cover of Paint It Black is great. I find that it’s the drums in the chorus that make the difference.
S^G
Similarly, Cyndi Lauper’s “I Drove All Night” is clearly the best, though Roy Orbison’s was first. Don’t even get me started on Celine Dion’s.
And featherlou, I respectfully disagree. Dolly Parton’s version of “I Will Always Love You” is far better than Whitney’s. Whitney is much more accomplished vocally, but Dolly’s is heart-breaking. Her voice is just so much more sorrowful, which is what the song calls for.
And I must respectfully disagree with you, my friend (are you feeling like one of those gophers, Mac and Tosh, yet? 
) I listened to your link with an open ear, and Dolly’s version is just too countrified for my taste. I’ll admit to being biased, though; I hate most country music. I hate that spoken lines in the middle of the song to sound more earnest thing that they do. I’ll agree that Dolly does have an interesting take on the song, making it much smaller and more heart-felt (even if that part felt manipulative to me). For me, what moves me about Whitney’s version is that it is almost unbearably beautiful, which also evokes a strong emotional response.
I like the Bangles version of “Hazy Shade Of Winter” better than the Simon & Garfunkle original.
This is a lot of fun.
And also NSFW.
It’s not bad, but it has a tragic lack of Mariachi trumpets. 
CSNY doing Woodstock is certainly the definitive version of Joni’s song.
I prefer Townes Van Zandt’s version of Dead Flowers. Makes me weepy.
But I came in here to recommend M Ward’s cover of Bowie’s “Let’s Dance”. Heard it for the first time on the soundtrack to Eagle vs Shark and was blown away. So sad…with Ward’s cracking voice just completely giving it a new meaning. The whole soundtrack is actually pretty outstanding…but that song blew me away.
I like Sarah McLachlan’s “Blackbird” better then the Beattle’s original. But it is probably because of Sarah’s ability to memorize me with her voice. I can’t find a non-live U-Tube version, but this mundane video uses it as the audio track, so just ignore the video and listen to the song.
Now, Sarah’s “Blackbird” is almost identical to The Beatle’s version; she did not “make it her own” as some have said makes a better cover. But Sarah did a cover of Gordon Lightfoot’s Song for a Winter’s Night, and my heart melts when I hear it. She sings it slower, and more passionately, in her own style. The original is still good, but the cover adds a sensitive quality that only an angelic voice can give.