NVD3 is an elegant visualization library that provides re-usable chart components based on d3.js. Here is an excerpt directly taken from the NVD3 website.

“This project is an attempt to build re-usable charts and chart components for d3.js without taking away the power that d3.js gives you. This is a very young collection of components, with the goal of keeping these components very customizeable, staying away from your standard cookie cutter solutions.”