OPTiSave
Macintosh freeware which visualizes quasi-conformal deformations of the once-punctured-torus groups. It interactively draws the isometric circles, the Ford region, and the limit set. http://vivaldi.ics.nara-wu.ac.jp/~wad...
SNAPSave
Exact computation of hyperbolic 3-manifolds and their arithmetic invariants. Written by O. Goodman in an ARC-funded project of Hodgson and Neumann. http://www.ms.unimelb.edu.au/~snap