Codpaste is a 14-part podcast about the history and practice of sound collage and mashups. A collaboration between Vicki Bennett (People Like Us, previously) and Ergo Phizmiz (previously), Codpaste is an entertaining and instructive wander through such topics as cartoon music, Negativland, easy listening, and William S. Burroughs. There's even a curriculum [30mb pdf] to go with it! Most episodes are about 30 minutes long, feature the same editing techniques and sound sources that they discuss, and are enhanced by Ergo and Vicki's wonderfully quaint accents.
Vicki Bennett is better known as People Like Us, and just so happens to be the anointed queen of Plunderphonics. Her music is comprised almost entirely of uncleared samples and has avoided lawsuit only by virtue of their (and her own) obscurity. Similar in style and sense of humor to The Evolution Control Committee and the (amazing, really, really amazing) Avalanches, you'll find nearly her entire body of work here.