This started as just a tech-demo, but now I think it might actually be useful.
I take the various API feeds from the exchanges and combine them into a live data stream.
Available here:
http://coinpro.mikeallisononline.comIt's still in the early stages of development, but I think it could be awfully useful (especially if more exchanges offered x-site web sockets/web services).
Exchanges, please feel free to let me know if you have live data streams that could be easily integrated. Since many of the feeds don't support CORS, I cache the data in 5min intervals to keep bandwidth concerns to a minimum.