Using http streaming/long polling with third party sites
I'm looking into long polling/http streaming/websockets and have a simple (I think) question that I can't find the answer to. Is it possible to make a "real time" application/widget that bolts on to a "static" third party site/database?
For example, is it possible to build an application that creates a real time front end for Facebook/Twitter/ebay etc... without the need to refresh to get new content?
I guess the solution comes down to long polling the third party server (??) but I'm not sure if that's possible (or even the right approach). Please could anyone point me in the right direction?
Thank you in advance for any help you can give me.