Very brief background: Craig Ferguson had the Mythbusters' Grant Imahara build him a robot skeleton sidekick. He teased it for months, and on the night the sidekick, named Geoff Peterson, debuted, this is how Craig introduced him.
This video is precisely why I love Craig Ferguson. He does what he wants, and what he wants to do is always goofy, funny, and cool as shit. The song is "Look Out, There's a Monster Coming" by the Bonzo Dog Doo-Dah Band. Really.