Great fun: the bobsled run in Donnstetten, in the middle of the Swabian Alb. It's a throughout-the-year-run, you can ride it whether it's winter or summer. Buckle up, loosen the brakes and speed up to 40 kilometers per hour (about 25 mph) on the 1160 meters long way down the green hill. Scream. Loudly!
I tried to take a video of the ride - more or less successful:
There is also another toboggan run just six kilometers away in Westerheim, combined with a small animal and amusement park. But the whole facility seems a little grubby - we don't recommend it.