Gephi - for all kinds of networks and complex systems, dynamic and hierarchical graphs

Gephi, is an interactive visualization and exploration platform for all kinds of networks and complex systems, dynamic and hierarchical graphs. It seems rather feature rich, with built in connectors to database systems, extensive graph coloring, layout, and rendering features, and several analysis tools. 复杂问题作图，有数据库接口。

(1)
Runs on Windows, Linux and Mac OS X. Gephi is open-source and free.

http://gephi.org/

(2) an interactive example
http://diseasome.eu/map.html

(3)
M. Hahsler, S. Chelluboina: Visualizing Association Rules: Introduction to the R-extension Package arulesViz