This kind of ties into a proof of concept I worked on a while ago.
An advantage of the native SETI-at-home clients is that they have access to the gpu. But theoretically so does javascript via WebGL so I took a stab at implementing matrix multiplication entirely on the GPU from within the browser. I think it could be a pretty powerful idea if it were fleshed out a bit more.
There was something similar to this posted a few months ago, http://maprejuice.com/. I believe it also used node.js and web workers in order to do distributed map reduce operations.
Yeah, myself and two others built the same thing for Node Knockout (maprejuice). In my opinion it's hardly an original concept at this point, but still a very interesting one with an interesting problem set.
I suppose its usefulness is closely related to the number of clients you could use it with. Would it be useful on a mom & pop's website? Doubtful.
Something with a measurable fraction of Facebook's scale might be able to get something useful out of it... assuming the users don't revolt when they discover it.
If you want to do some actual high-performance work, I'd look at Java applets. Java runs around 5x faster than the same JS code (V8), and much much faster in browsers like IE. Plus they have real multi-threading.
An advantage of the native SETI-at-home clients is that they have access to the gpu. But theoretically so does javascript via WebGL so I took a stab at implementing matrix multiplication entirely on the GPU from within the browser. I think it could be a pretty powerful idea if it were fleshed out a bit more.
http://learningwebgl.com/blog/?p=1828