As a Badger, I'm proud to say that the Onion started at the University of Wisconsin sort of as our answer to the National Lampoon. The building where they started was razed a couple years ago to make way for a high-rise apartment building. I have it on good authority that one of the founders went on to be a writer for Futurama's recent comeback and for American Dad.
EDIT: They still have an office in downtown Madison. It's called Zweifel, Zweifel & Zweifel.