Dena and I went to the House on the Rock in southern Wisconsin two weekends ago. It's a 3-4 hour drive from Chicago and takes about the same amount of time to tour, if you get the Ultimate package (includes the three tour plans).
The house is the creation of eccentric architect Alex Jordan, and it is filled with artifacts and exhibits that will make you what Mr. Jordan was smoking. The world's largest carousel, a collection of doll houses, antique and replica weapons, and more.
The Organ Room, is one of the most peculiar things I've ever seen. Pianos mounted on the walls and set on the floor. Giant copper tubs that appear to be part of a distillery but connected to electrical generators. It's easy to imagine that all sorts of dark and strange rituals conducted by an evil maestro using this or this.
to conduct his undead orchestra in the middle of the night.
Dena's pictures are here, if you're so inclined.