A Simple 3D Model Viewer
Here's a cute little app. It
reads wavefront .obj files which describe 3D models and displays them as a wireframe.
If you hold the left mouse button down and move it around, you'll rotate the model as
though it were inside a sphere and you were rubbing the top, much like a track-ball.
It does a limited amount of depth cueing.
If you'd like to look at the source for the modeler, it's right
here.