From listening to the Daily Source Code, Adam Curry's podcast I've once again been entertained by mashups. A mashup is a mix of different songs combined into one, to hopefully create a piece of work that is greater (or at least equal to) the sum of it's parts.
I first got really interested about this when a friend told me about the Grey Album, a mashup of the Beatles' White Album, and Jay-Z's Black album done by DJ Danger Mouse. One that Curry played that I really enjoyed, was a mashup of Mariah Carey and Cyndi Lauper. Now I don't like Mariah much, but this is really good. Check it out at here.