Whoa,

this looks interesting. There is a festival of online performances called UpStage taking place on August 8-9. I haven't heard of this before but according to the website UpStage is an open source server application that allows you to watch and interact with other people's performances live on a web page, without downloading any special software (you just need a Flash player plug-in or whatever). You can also download the program for free and use it to make your own art pieces, though I don't know what creating said pieces actually means in practical terms; I'll have to try it myself and see. I like this too because it's licensed under a Creative Commons copyright! Fight the power!