paramiko/paramiko — pull request #68 by grandrew (2012-05-10 19:33:47+00:00)
Title: Support for non-blocking connect to 1000+ hosts simultaneously using asyncore

I added SSHClientAsync class that is compatible with python asyncore. I already tested it on 1000+ simultaneous connections with very low memory consumption and totally asynchronous (no problems with unresponsive hosts, etc.).
The next task would be asyncore enabled Transport class to further enhance mass-interaction.