Crazy Idea of the day

Having been reading about Google's Omega project on wired, I was thinking about how I could build a rival super computer using my meager resources. How could I get my hands on thousands of processors to perform large parallel computations.
How about using browsers as nodes on a web wide computer.

1. A visitor to my server opens a page and confirms that they are will to take part in the process.
2. The web page polls the server for tasks.
3. When a set of tasks are available, the tasks are shared by the server among polling browsers.
4. The tasks are sent as small JavaScript programs to run.
5. The results are sent back to the server for collation.

The web page would display details of the tasks being run.

The service could be offered as a peer to peer service, with a web interface offering the ability to upload jobs to be run.