I tried for a while (unsuccessfully) to get any sort of graphics working with Lisp. Do any of the games in here use graphics? I feel like some really awesome "math art" could be made with Lisp.
http://code.google.com/p/lispbuilder/wiki/UsingLispbuilderSD...
For realtime 3d graphics there's cl-opengl (http://common-lisp.net/project/cl-opengl/). I'm using it right now with sbcl and the glut wrapper (cl-glut). It comes with some examples too.
This project might get you started:
http://createuniverses.blogspot.com/2009/09/qtimagine-skelet...