After arriving in Chicago, I went to the Segway store you mentioned. They didn't rent Segways out. Two hours later, I emerged with a $500 bill and a Segway for 7 days.
I went to Kinkos and printed out a thick cardboard front with "BrunoBooks.com" on it and taped it to the front of the Segway. I gotta say, riding those things is a LOT of fun.
Unfortunately, I underestimated how bleeping cold it is in Illinois in early January, and therefore failed to realize the implications of what I'd done. For the next week, I rode around in sub-zero temperatures handing out fliers. I'd had the choice between University of Texas and Illinois, and I'd made an unforgettable mistake.
Follow-ups to this story:
1) It didn't really work. Of 40k students, ~500 visited our site. After conversions, this was terrible for business.
2) Everything is negotiable. For the right price, you can rent anything. In a larger sense, don't take no for an answer.
3) Don't be an asshole to people handing out fliers. Usually they're just doing their job, but even if it was their idea there's no need to be a dick about it.
4) Don't ride a Segway around U of I in January.