1. Graphviz - Graph Visualization Software 2. Inkscape, http://www.ioncannon.net/utilities/123/10-tips-for-creating-good-looking-diagrams-using-inkscape/ 3. [[http://www.gimp.org/)][GIMP ]] 4. [[ http://www.blender.org/][Blender]] 5. [[http://www.texample.net/tikz/][Tikz]]- the most complex and powerful tool to create graphic elements in LaTeX 6. Visio 7. Processon.com -Online tool 8. Asymptote References: Nice scientific pictures show off