Hi utu. Thanks again for your reply.

I have always used the no3d cheatcode so we can rule out Compiz. I do have a defective touchpad which sometimes gives signals when I'm not anywhere near it. However, I do believe that while the icons are flying, I can maintain control of the mouse pionter with my USB mouse (unlike when the touchpad is firing). I now have the touchpad disabled on startup. If I see them again, I'll pay close attention to what else is happening on the computer.

The post you referrenced was describing flying windows and panels, not icons. These icons are by far the strangest thing I have ever seen on a computer.