Graphic Design

GIMP [My Pick!] for Mac OS, Linux, Windows
GIMP is the GNU Image Manipulation Program. It is a freely distributed piece of software for shttp://www.blogger.com/img/gl.link.gifuch tasks as photo retouching, image composition and image authoring. It works on many operating systems, in many languages.
http://www.gimp.org
Tips: Use MacPorts to install GIMP for Mac OS.
MacPorts
http://www.macports.org/
All you have to do is type:
port install gimp
DarwinPorts will do the rest, which may also include building various dependencies. This can take quite a while (several hours).

Inkscape [My Pick!] for Linux, Windows
Draw Freely.
http://www.inkscape.org