Yet another try to develop a .NET IRC Bot with full plugin capabilities.
CuteIRC is a multi-server IRC client which supports also CTCP and DCC. It's multi-platform oriented (Linux, OS X, Windows) and full-featured but easy to use.
Octyne is a powerful IRC to Internet Data connection service.
Trivex is a open-source IRC bot coded in Visual C#.
A little Service set for TS6 IRCd Servers (like InspIRCd 1.2)