I have had the good fortune to explore a bit of HTML5, an emerging web standard that is poised to take the online world by storm. The technology isn't quite there yet. Current browser vendors offer differing or incomplete implementations of the standard and it's a bit of a pain to ensure that whatever you write works generically. Still, this is one of those lemons that bears watching...
The project has been hosted on Google App Engine and can be accessed from the following URL: lightsnakegame.appspot.com (I wanted to get the app name 'lightsnake', but someone seems to be squatting on it).
EDIT: The source of the project can be forked on github at: http://github.com/angelorohit/lightsnake