I wrote a small iPhone app a little while ago called FireWater, for which I developed a simple pressure-based fluid simulation. I thought it would be fun to port it to the HTML5 Canvas in Javascript to learn the Canvas myself and teach a little about writing simulations. That's jsWater. If your browser supports HTML5 canvas, but the canvas above is not filled with black, please refresh your browser. Once you have a black canvas, click and drag on it to see it in action. You can see it in action at UpFork: http://upfork.com/articles/javascript-fluid-simulation-for-html5-canvas