Suggestions for a Linux Cluster:
POV_Ray rendering (Photo-realistic images basied on 3D raytracing):
www.povray.org
Blender (3D Modeling) rendering (you could go almost real time here!):
www.blender.org
Mathematica 5 (equation solver-commercial software):
http://www.wolfram.com/
Just a few ideas.
I would have this professor put out a staff bulletin and ask other departments if they have uses for a high-performance machine like this. Basically, anything that involves really complicated mathematics that can be broken down into parts (like machine 1 renders pixeel 1, machine 2 pixel 2, or machine 1 solves for square 1, machine 2 square 2, etc).