JavaScript InfoVis Toolkit

http://thejit.org/demos/

JavaScript Diagram Builder 

http://www.lutanho.net/diagram/

Raphaël—JavaScript Library

http://raphaeljs.com/

Data-Driven Documents

http://mbostock.github.com/d3/

Graph

http://nodebox.net/code/index.php/Graph

Protovis

http://mbostock.github.com/protovis/