0mq is something that I've had the pleasure of working with for some time since d4de introduced me to it. Basically, 0mq is a new socket(think BSD socket replacement) that uses its own over-the-wire format(so it's not directly IP-compatible) but permits a great deal more functionality and speed. 0mq sockets can be multi-connect, meaning you can connect a single socket to multiple different nodes simultaneously. The speed is phenomenal and several socket connection paradigms are easily implemented, like push/pull & pub/sub. It's really quite fantastic and definitely worth the look. I might also suggest looking into libxs/crossroads. But read the documentation on 0mq first, it's worth it.
