What I've got isn't general-purpose at all. I'm working on distributed learning algorithms, and right now I'm more concerned with having lots of nodes in the learning algorithms than I am in simulating real-world p2p...so I'm not modeling things like network delays, nodes dropping out and returning with different IPs, etc.

How about you?

If I get something that might possibly be useful for someone else, sure, I'll put it on github or something. (If I get a good design, the real network will be opensource too.)

Would that be for a university assignment, to design your own protocol or for something else?