//Non-Flash charts is a favourite topic of mine (see more here http://bit.ly/g-chart), basically because charts have been one of the last things Flash could do that HTML couldn't. This of course has been changing a lot the last few years. 

Another very recent (released yesterday!) example of is Chart.js. It packs: 
– 6 animated chart types: Line, bars, radar, pie, polar area and doughnut
– Canvas-based vector output which means crystal clear graphics at any resolution
– Cross-browser support on modern browsers, support for IE8 and below through ExplorerCanvas
– No Flash = Mobile-ready (kind of obvious since it's HTML5 but worth noting) 
– Lightweight and very good documentation (for a 0.1 release) 

Get Chart.js here http://bit.ly/chartjs

(Found via +Michael Mahemoff and +Stephen Bond)