Cool: David Bowie has just launched a new mash-up contest. There's a new ad campaign for Audi cars that features two of Bowie's songs mashed-up. They've decided to throw a mash-up contest to capitalize on this, awarding a new car to the best song that uses samples from his new album and any older Bowie song. Voting on entries starts this weekend and the contest ends next month so get your turntables cranking.

Mash-ups are hybrid songs that generally feature one artist's vocal track (or a cappella) electronically grafted to the instrumental track from a different artist's performance of a different song. Digital pitch-shifting and time-stretching ensure that both artists are performing in the same key and at the same tempo; the trick is to find two songs with similar harmonic structures, although their styles may be wildly varying. In this case David Bowie is being mashed with his own music, but in some cases the brave listener can find some really far out mashes.