Springy: A force-directed graph layout algorithm in JavaScript
getspringy.com
getspringy.com
(BTW, see http://bl.ocks.org/mbostock for an impressive collection of visualizations made with D3.js. Impressive both in terms of size of the collection, quality of the code and clarity of the visualizations.)
https://github.com/dhotson/springy/commits/master?page=4 https://github.com/mbostock/d3/commits/master?page=91
If all you need is spring layout without the rest of D3, Springy might be a better fit.
Just found it interesting.