Charts Factory - Create simple charts super fast and for free!
D3.js - D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG, and CSS.
FnordMetric - Create charts and dashboards from SQL
Chart.js - Easy, object oriented client side graphs for designers and developers.
Mountain - Living seamlessly in the menu bar Mountain allows you to manage volumes with ease.
Google Charts - Interactive charts for browsers and mobile devices.