If you're talking about Aero mode, you just need windows+tab. It's just a trippier version of alt+tab.
Edit: Well ok, you add ctrl if you want it to not go away once you release the keys, then you can just tab through the windows. And you have to make sure you're pressing tab last.
Edit2: Oh the mode is actually called Flip 3D.
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Worry is a misuse of imagination.
Fantasizing about Guru champion BlAcK TuRtLe, however, is a great use of it.