Tornado - Non-blocking Web Server powers FriendFeed

Tornado is an open source version of the scalable, non-blocking web server and tools that power 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 thousands of simultaneous standing connections, which means it is ideal for real-time web services. Tornado is one of Facebook's open source technologies.