Girl Talk’s latest album Feed The Animals is awesome. It’s also made up entirely of samples (list of some of which can be found at wikipedia). It’s not going to be available for long is my bet, so download it while you can.
It’s on a “pay as much as you want” basis, but $5 gets you FLACs.
As a piece of music it’s fantastic; as an exercise in sampling it’s technically faultless; and it’s a trainspotter’s paradise. Get it while you can.