KSeg Geometry Sketchpad
Sketchpad for planar Euclidean geometry
KSEG allows you to interactively create a geometrical construction,
similar to what you can do with a straight edge and compass. Points
may be inserted on the page with right mouse-button clicks, and then
used to form segments, lines, circles, or other geometrical objects.
At any time you can drag existing points around, and watch how the
constructed objects respond.
See http://www.mit.edu/~ibaran/kseg.html for more info.
