Jay-Z & Linkin Park - Collision Course

  Mash-ups -- two songs stuck together that were never meant to be stuck together -- have their roots in the bedrooms and basements of computer-savvy music geeks who spend countless hours sticking Christina Aguilera's vocals over the Strokes' chugging backbeat or Missy Elliott's raps over George Michael, Joy Division, the Cure, and about a thousand others. MP3s were the medium of choice, white-label 12"s a distant second. It seemed like it was time to put a fork in the pranky genre when collections like The Best Bootlegs in the World Ever and Soulwax's As Heard on Radio Soulwax series exposed the mash-up to a wider audience, but then Danger Mouse came along. His headline-making Grey Album -- Jay-Z's Black Album vs. the Beatles' White Album -- inspired a ton of spirited imitations, and most likely the MTV-spawned, artists-involved Collision Course. The fact that the artists are involved with the project totally goes against the mash-up philosophy, but luckily Linkin Park -- who are reve