ZGRViewer is a 2.5D graph visualizer implemented in Java and based upon the Zoomable Visual Transformation Machine. It is specifically aimed at displaying graphs expressed using the DOT language from AT&T GraphViz and processed by programs dot, neato or others such as twopi.
Open source graph visualization software. Takes descriptions of graphs in a simple text language, makes diagrams formatted as images, SVG for web, PS for PDF, GXL (XML dialect), and more.