d3-sankey
A fork of D3js's Sankey plugin
Demo: http://bost.ocks.org/mike/sankey/
var sankey = d3.sankey()
.size([width, height])
.nodeWidth(15)
.nodePadding(10)
.nodes(energy.nodes)
.links(energy.links)
.layout(32);
var path = sankey.link();