Geometry calculates area, surface area, and volume for geometric figures which include prisms, pyramids, cones, cylinders, and spheres.
Interactive geometry software for GNU/Linux, XO laptop, Windows and Mac OS X.
It is based on the geometry of a Spirograph with varying wheel sizes.
A fast Asteroids style game with influences from the likes of Geometry Wars
Using Caedium add-ons you can create any 2D or 3D geometry