Searching "rap covers" online is like walking into a minefield of acoustic guitars and webcams, leftovers from a war that began with Ben Folds' famous version of Dr. Dre's "Bitches Ain't Shit." An earnest-sounding white dude with a guitar and an angelic backing choir singing things like "Lick on these nuts and suck the dick" was (believe it or not) novel at some point, but now that approach has been beaten to death. Last year, for example, a ten year old covered "Trap Queen."

But Punk Goes Crunk aside, the more interesting version of a "rap cover" is the flip side, when contemporary hip-hop and R&B artists decide to cover classics from the past. Sure, plenty of rappers sample originals from 20th century greats, but attempting a full cover goes a step beyond that. There are plenty of horrible examples of this, most notably Jay Z's god-awful (albeit tongue-in-cheek) "Wonderwall" cover from Glastonbury several years back, but also plenty that have turned out great. Just yesterday, in fact, Trey Songz delivered a show-stopping version of David Bowie's "Life On Mars?"

Here are ten more solid covers from some of our favorite artists. Let us know if we missed any of your favorites.