Qhull 2003.1 - Qhull computes convex hulls,
Delaunay triangulations, halfspace inter-
sections about a point, Voronoi diagrams, 
furthest-site Delaunay triangulations, and 
furthest-site Voronoi diagrams.  Qhull 
works with 2-d, 3-d, 4-d, 5-d, and higher 
dimensions.  It computes volumes, surface 
areas, and approximations.  It runs in a 
DOS window under Windows 95/NT/XP.
www.qhull.org, freeware.