The Aztek, hands down. The Honda Element is in there, too. The old Volkswagen "Thing" had a deliberately cultivated ugliness that disqualifies it, IMHO, and besides, I like 'em.
I like the Thing, but then I like the Element as well. The price and practicallity are hard to top. I currently own a Volkswagen Vanagon Syncro (all wheel drive) Westfalia and a Honda Insight, so my taste in autos is considered suspect by some. :^)