Is it possible to use 3D objects in OS X's UI? I should imagine that adding them just as a picture would work, after all OSX is not a 3D environment itself, but, will it accept the COLLADA .dae format itself?

Snow Leopards QuickLook feature recognises the .dae format, it's even able to rotate the design, but, can this be done in say a programs UI e.g.

If the Address Book just happened to have a Chair (http://sketchup.google.com/3dwarehouse/ ... a06adfd0f4) in it, imagine that, draggable with the mouse cursor so it rotated on it centre axis.