Fons Adriaensen:
 Anyone knows a good vector drawing program for Linux ?
 Absolute requirements are:
 - Lines, arrows, boxes, circles, etc.
 - Linewidths and styles, colors, filling.
 - Text
 - PDF or PS export.
 - PNG and JPEG import (no bitmap editing required).
 - Accuracy.
 I've been using TGIF for years, but I'm more and
 more being blocked by its main flaw which is that
 it seems to use a unit of 0.2mm internally (in
 metric mode) which is orders of magnitude too big.
 Tried QCAD and INKSCAPE, both fail basic
 requirements (and have other problems).
 
Maybe pgf / tikz would be useful?
http://www.ctan.org/tex-archive/help/Catalogue/entries/pgf.html