Girl Talk's been doing mashups and concerts for years, and he's got a brilliantly exacting sense of timing and a knack for finding unlikely cuts to mash up. I hear the sixties in there; you'll hear whatever music was popular when you were seventeen. Remarkably, he's sampled dozens of popular artists without being subjected to the large licensing demands that usually come with sampling. It turns out to be easier to make music these days if you're judgment-proof; he just stopped worrying about legal rights and released his music. But the music industry deserves some credit for letting him continue to sample unmolested. (He's apparently offered some small fees that reflect his returns to sampled artists.)
Girl Talk isn't for everyone. You'll like it if you like M.I.A. and have to have a high tolerance for bad language, of both the old school (the seven dirty words) and the new school (ethnic and racial slurs). Even then, some of the material is too hip-hop for me.
I wanted to post a clip or two here, but Blogger only allows the posting of videos, not mp3s -- I assume that's the result of music industry antipiracy scrutiny. But the good news is that you can sample the music free. Girl Talk's album is available (in a Creative Commons license) on a "pay what you want" basis here. So you can pay nothing, download the album, and decide whether it's worth anything to you. Then you can go back and pay -- and they'll throw in bonuses if you pay more than $10. Of course, you'll have to explain to your spouse why there's a charge for "Illegal Art" on your credit card. That's Girl Talk's label.