Devo guest stars as a musical guest and plays "Beautiful World" during the Futurama 100th episode. Oh and they're mutants on the show.
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A clip from the Futurama season finale in which the Planet Express crew makes its hundredth delivery.
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Futurama Season 7 Episode 12 Quotes

This calls for a party, baby. I'm ordering 100 kegs, 100 hookers and 100 Elvis impersonators that aren't above a little hooking should the occasion arise.

Bender

Professor: We've been hired to make our 100th building delivery!
Hermes: That's nearly ten per year.