While preparing for Nirvana's 1993 appearance on MTV Unplugged, frontman Kurt Cobain was reportedly so worried about translating the songs into an acoustic setting that he almost asked drummer Dave Grohl to sit out. Grohl played, but the point remains: Sometimes the most effective way to reveal the heart of a song is to strip it to its core. Here's a collection of contemporary rock tracks, pared down and reinvented by the original artists. Our editors regularly add new tracks to this playlist. If you hear something you like, add it to your library.