GEUP - Interactive Geometry software. - GEUP is an interactive geometry tool. Lets you dynamically explore Mathematics, build mathematical models of real world or create interactive mathematics presentations. - http://www.geup.net
Qhull for convex hulls, etc. - Qhull for computing the convex hull, Delaunay triangulation, Voronoi diagram, and halfspace intersection about a point. - http://www.qhull.org
GEUP - An interactive geometry program for Windows. Evaluation version free to download. - http://www.geup.net/index_eng.htm
KwikTrig - A free trigonometry solving program for Windows. - http://www.fracaro.net/kwiktrig.htm
Riemann surfaces visualisation - Unifpack is a set of programs and C libraries designed to help in the study of Riemann Surfaces. - http://www.geom.uiuc.edu/apps/unifweb/about.html
KSEG Interactive Geometry Software - KSEG is an Open Source program for interactively exploring geometric constructions which can be used to teach geometry in the classroom or for personal enjoyment. - http://www.mit.edu/~ibaran/kseg.html
WinGCLC - a tool for describing geometric constructions and making digital illustrations in LaTeX and bitmap format. - http://www.matf.bg.ac.yu/~janicic/gclc/
GANG Software Suite - A set of mathematical environments for computing, visualizing and experimenting with geometric objects; built with the OpenGL/Mesa library and the GTK+ user interface. - http://www.gang.umass.edu/software/
Symmeter - An on-line tool for understanding and measuring symmetry. - http://www.symmeter.com/
Home Page of Isard - A free dynamic geometry package for Windows, PowerMac and Linux. Like Cabri, but in Smalltalk (and smaller). Source available : you can extend it as needed ! - http://www.jeannot.org/~js/isard/
Geometria - A Java program in solid geometry. Solids can be measured, cut, drawn upon. 60 sample problems with resolutions. - http://geocentral.net/geometria
The Geometer's Sketchpad Resource Center - This Resource Center supports users of The Geometer's Sketchpad "Dynamic Geometry" software. Contents include a freely-downloadable demo and Java versions; research bibliography; online activity guide; technical support center. - http://www.keypress.com/sketchpad
MowMowMow's Cabri Room - Many Cabri files aimed at high school level geometry. - http://www.mowmowmow.com/math/cabri/index_e.htm
Ricci - A Mathematica package for doing tensor calculations in differential geometry. - http://www.math.washington.edu/~lee/Ricci/
Polyhedron - Interactive application for solid geometry with 250 built-in problems. Simulates ruler, compass, protractor and other tools. Solids can be cut, displayed differently, rotated, joined again. - http://www.geocentral.net/polyhedron
Cinderella: Interactive Geometry - Cinderella is a Java based interactive geometry tool. The only available tool that gives correct solutions to typical geometrical problems. - http://www.cinderella.de/
Great Math Programs - A collection of mathematical programs, with particular reference to geometry. - http://www.xahlee.org/PageTwo_dir/MathPrograms_dir/mathPrograms.html
Singular - Computer algebra system for polynomial computations. Free download. - http://www.singular.uni-kl.de/
C.a.R. Geometry Program - A free program allowing Compass and Ruler constructions. Now also available in Java. - http://mathsrv.ku-eichstaett.de/MGF/homes/grothmann/car.html
Cabri Geometry - The home site for Cabri Geometry, a dynamic geometry package . - http://www-cabri.imag.fr/index-e.html
Cabri Java beta version - Create dynamic geometrical figures using Cabri and publish them as Java applets. - http://www.cabri.net/cabrijava/