If you are looking for a FREE 3D vis package, you might consider VolVis.
Their website is listed below.
http://www.cs.sunysb.edu/~vislab/volvis_home.html
It runs on a variety of Unix platforms including Linux! IDL is a nice
package though.
- Derek Schulze
Flow Cytometry and Confocal Microscopy Core Facility
Cancer Research Labs
Queen's University
Kingston, Ontario
Canada