The Flat Top Barge makes a nice dance floor: ...and aircraft carrier, too. The windmill was achieved by: Spawning a Pessima. Installing the Stunt Mortar mod with the default settings. Remove the rear bumper (Parts menu or node grabber). Node grab the center of the chassis that was behind the rear bumper. Pull the rear of the Pessima up until it's at 45 degrees. Stick the node you grabbed in mid-air with 100% force. Start spamming the Stunt Mortar. The car will start spinning while the grabbed node will hold the center of spin. The motion gets smoother as the nose gets rounded. The other dance moves are pretty easy to figure out, and still more dance moves may be possible. Everything I did in the vid was with the Stunt Mortar. It's designed to be versatile. If you put together an awesome dance routine, post it to this thread. Synchronize to the beat for bonus points!
I'm glad that you enjoyed the dance party. I'm sure that I'll smash another dance floor once I figure out some more moves. [Insert techno music here]