The only one I've been to is the one on top of the Schilthorn in Switzerland. It was also Blofeld's lair in a James Bond film. You can watch scenes from the movie at the restaurant (in another room, thankfully) and they serve a James Bond Brunch.

As I recall, it was expensive and the food mediocre. You pay to be revolving at the top of the Alps. The view is second to none, though.

http://www.schilthorn.ch/?uid=32