Wouldn't a Kelly Clarkson/Paramore cover be fantastic? Either covering either. They're just different enough musically--one slightly more rock, one slightly less--that it'd be interesting to hear, but they're similar enough that it'd completely work.
Clarkson, as it turns out, usually does a cover at one of her shows. Standard stuff. This time, it was Paramore's "The Only Exception," which somehow makes a lot more sense from her than from Paramore. It could've been on Stronger easily, couldn't it? Maybe one of the last tracks, right after the guitars and angst have subsided. Watch below.
(Incidentally, for those of you who are X Factor obsessives--it's a Kelly Clarkson post, so the odds are a tiny bit higher here--here are The Brewer Boys, those guys you remember, with Kelly and Paramore, tying this post up nicely.)