http://amcharts.com/ http://amcharts.com/ is one example I can think of. You can use it for free if you don't mind "charts by amcharts" in the corner. This ma

http://amcharts.com/ http://amcharts.com/ is one example I can think of. You can use it for free if you don't mind "charts by amcharts" in the corner. This makes it possible for free personal use, as well as the ability to try it for free, but if you want to use it on your business site or software, most would surely pay the fee.