Connect to one server with many clients under one nick transparently
Connect to multiple servers using only one process
CTCP support when no client is attached
irssi-style logging support
Transparent detaching and attaching of clients
Password support
Replication support
Auto-Away support
Keeping track of events occuring
Direct, inetd-style interfacing with local IRC servers (such as bitlbee)
Responses to queries are only sent to the originator of the query
SSL/GNUTLS support