Piz Gloria / Schilthorn summit, Switzerland. This is the only revolving restaurant I'll ever admit visiting, and the only time I'll ever link to a James Bond website... The cable car to the top is very expensive, and the best discount is with a SwissRailPass (rather than a EurRail pass). The views are spectacular; check the webcam online to make sure the weather up top is clear before you go. The Bond movie is a must-see - vacation homework!