Here are some celebrities who should be drawn like Terrance and Phillip, ie. dots for eyes and a head that splits apart when talking:
Pamela Lee Jim Carrey Peter Jennings William Shatner Alanis Morisette Jason Priestley Michael J. Fox Bryan Adams Mike Myers Shania Twain Sarah McLachlan Dan Aykroyd k.d. lang Wayne Gretzky Neil Young Leonard Cohen The Barenaked Ladies Geddy Lee/Rush
to name a few.
Or how about this? Take Robert Smith's hair from "Mecha Streisand" and slap on Terrance or Phillip's face, and you have Nivek Ogre of Skinny Puppy. :)