Over at markstar.co.uk, you can see some cool experiments that Mark has been working on, and frankly the source code behind them is very cool.
The experiments themselves are based on the HTML5 Canvas element, and its drawing tools. The experiments are part of a series, exploring the initial Canvas element, and then quickly moving into some more familiar Flash-style drawing features, before exploring the possibility of converting the Flash HYPE Framework into an HTML5 Canvas version. All pretty interesting - can't wait to see if he gets onto some of the really cool complex examples of the HYPE Framework.
You can check out the series of experiments in the Canvas tag archive here.