Slicer2-nohistory is a project mainly written in TCL and C++, it's free.
An old version of 3D Slicer (no longer actively supported) - here for reference
This is a snapshot of an anonymous checkout of the slicer2 cvs repository checked out with these commands:
cvs -d :pserver:[email protected]:/projects/cvs/slicer login
Enter 'bwhspl' as the password and then
cvs -z3 -d :pserver:[email protected]:/projects/cvs/slicer checkout slicer2
3D Slicer version 2 is no longer actively developed, but is still available for binary download at slicer.org.
A lot of training material is available, which serves as examples of what is possible with the platform:
http://wiki.na-mic.org/Wiki/index.php/Slicer:Workshops:User_Training_101
Many of the 207 slicer-related publications at this site were based on slicer2:
http://www.na-mic.org/publications/pages/display/?collection=11&entriesPerPage=50