It's funny to think that back in the '60s, nobody ever heard a song and thought, "Oh shit, so-and-so should remix this." These days, especially for people that grew up on hip-hop and electronic music, it's a common thought. Sometimes you can't help but hear a new track and immediately start imagining a rapper on it. We're experiencing no shortage of rappers, and that means every time a song with a rap-friendly beat blows up, MCs flock, but it also means that every now and then we get a mind-blowing remix that changes the way we think about a song. Here are 15 tracks that we're hoping get remixed. Rappers, take note.