This was apparently on the ForceCast last year, although it was brought to my attention sometime ago by the one and only Koonfan. Without giving too much away, it's a rendition of Dr. Seuss's How the Grinch Stole Christmas, by James Arnold Taylor (Obi-Wan Kenobi) and Corey Burton (Cad Bane/Ziro). Hilarity ensues. A Youtube version of the broadcast can be found here. Listen at your own risk. Merry Christmas, y'all.