By far the best fair ride is the Zipper. I feel passionately about this. It has a vertical support with an axle in the center. Rotating on that axle is an oblong shape around which a belt runs, and that belt continually makes circuits of the oblong shape. Attached to the belt are cars, which each have their own axis of rotation and spin independently of each other. So, when the ride is running, you are spinning in three separate motions concurrently, and the individual cars often get hurled around the end of the oblong by the rotating belt and sent into a fast spin on their own axes.
I think what I find so great about it is that there are so many different motions going on tat it’s impossible for your brain to figure out what’s going to happen next. So much spinning! It’s close to the perfect ride.
Not one for the faint-of-stomach, of course.
You can see one here: http://flickr.com/photos/sutanto/1122914225/