Came across this 2 sites by Carlos Ulloa showcasing real time 3D in flash:
http://www.helloenjoy.com/ greets the viewer with an interesting transition from plain 2D words into a few 3D reflective text blocks floating in a white environment. After panning around them for awhile, the viewer soon notices that the cursor changes when hovering on each letter, and discovers in delight that those are not just floating 3D objects looking pretty, they actually demonstrate an interactive physics engine. Try them out yourself.
http://www.carlosulloa.com/ looks normal, until you decide to give the controls a try. Go ahead and be surprised.