[Twisted-Python] Twisted-friendly Message bus

[Phil Mayers]

All,

I've run into "this service needs to know about this event from this 
other service" once too often. It's message bus time, baby.

However, many of the daemons I use are locally-written Twisted code, so 
a Twisted-friendly (async api) one would be nice. Note also that other 
non-Twisted code will need to connect to it, so rolling my own (aside 
from it being a bad idea from a NIH perspective) is out.

I could of course wrap the message queue receiver for something 
well-proven like Spread into a thread. Then there's XMPP which is the 
darling of the anti-Java movement - though wrapping Twisteds' XMPP API 
to get a message bus might be annoying.

Suggestions?