Description:Tornado is an open source version of friendfeed web server and some of the tools use most often at FriendFeed. The framework is distinct from most mainstream web server frameworks (and certainly most Python frameworks) because it is non-blocking and reasonably fast. Because it is non-blocking and uses epoll, it can handle 1000s of simultaneous standing connections.

Usecase:

Source code: http://github.com/facebook/tornado