Raytraced Water Simulation (WebGL)
Update (2011.08.22): the latest update of Firefox 6 supports now the OES_texture_float extension.
Here is a cool WebGL demo that shows a water simulation with raytraced reflections and refraction. Currently this WebGL demo works only on Chrome because it requires the OES_texture_float WebGL extension. Fortunately for Firefox users (Firefox prior to 6 or other browsers that do not support the extension), the developer has youtubed his demo: