LISA POPEIL AND WEIRD AL YANKOVIC

Here's Lisa Popeil, singing background on Weird Al Yankovic's 'Tacky'.
(Lisa did the vocals on Zappa's 'Teen-Age Prostitute'.)

The video features
"Weird Al" Yankovic, Aisha Tyler, Margaret Cho, Eric Stonestreet, Kristen Schaal and Jack Black

And just for fun, here's Weird Al's Zappa tribute, from 2003.
With Dweezil Zappa on the guitar.