I found this article on what is now being called "COMET," essentially a variation on Ajax in which an HTTP connection is kept open between browser and server and the server-side application sends near-real-time updates through some type of server push. As the article mentions, most existing web servers and web-development frameworks are built to close out each response as quickly as possible and thus are not equipped to handle this type of setup. But it also says that tools exist to enable this today and specifically mentions POE. I don't know much about POE, so I'm wondering: can it be used for an application of this sort? which components does one need? Loosely speaking, how might such an application be laid out?