Overview:
The graphael system implements several classic force-directed layout methods, as well as several novel layout methods for non-Euclidean geometries, including hyperbolic and spherical. The system can handle large graphs, using multi-scale variations of the force-directed methods. Finally, the system can layout and visualize graphs that evolve though time, using static views, animation, and morphing.
The latest postings for this project were dated 2005.
Would be interesting to compare the capabilities here with those of later graph visualization projects.
Perhaps even a topic map of graph visualization projects to study the duplication of layout methods over time?