After some hours of development here come a small experiment in javascript using canvas and ImageData.You'll find more information on voxel.onaluf.org.

ps. the screenshot is from an higher resolution as what you'll find online. That's because it's really slow otherwise :) ...

I just published on jQuery's plugins site the alpha version of gameQuery. It's a plugin aimed at easing the development of javascript games. The goal is to give a practical alternative to flash in some specific situation.

Using gameQuery and jQuery allow a higher level and cross-browser approach to the game display.

You can find the gamequery main page here

This is a technical demo of gameQuery usage: