SNetworkX is a port of the popular Python graph library NetworkX. Lets describe it with their words:
NetworkX is a Python language software package for the creation, manipulation, and study of the structure, dynamics, and function of complex networks.
With NetworkX you can load and store networks in standard and nonstandard data formats, generate many types of random and classic networks, analyze network structure, build network models, design new network algorithms, draw networks, and much more.
Looks like an easy way to include graph representations of topic maps in a web page.
I suspect you will be seeing more of this in the not too distant future.
I first saw this in a tweet by Christophe Viau.