LayerCake is A simplistic online image manipulation program where players see the edits of others in real time. Artists create a LayerCake by uploading several layers as PNGs and specifying some preferences, then Players may interact by picking layers and messing around with the transparency, brightness, blur and so-on in various ways. More types of manipulation to come soon!

See http://nathannifong.com/LayerCake to play it live

It consists of a HTML5/JavaScript game that communicates with a python-twisted server using Websockets.

The supporting website consists of some PHP, and a MySql database.

Requirements: Client-Side: Browser that supports Websockets and Canvas elements. (Chrome recommended) Server-Side: Python 2.4+ python-twisted PHP5 MySql