very good CAD software
Drawing, graphics conversion, software development, administration.
A simple LaTeX {picture} drawing tool
2D CAD for precise drawing
a race scenario drawing tool
Vector drawing program for LaTeX using PSTricks
Simple and intuitive 2D vector drawing for electronics and not only.
Syntax Tree Drawing Software (Linguistics)
Free drawing software for Windows, Mac OS X, and Linux
Vector based drawing software designed for RPGs