Dia (diagram creation program)

Dia is inspired by the commercial Windows program 'Visio', though
more geared towards informal diagrams for casual use. It can be used
to draw many different kinds of diagrams. It currently has special
objects to help draw entity relationship diagrams, UML diagrams,
flowcharts, network diagrams, and many other diagrams. It is also
possible to add support for new shapes by writing simple XML files,
using a subset of SVG to draw the shape.
