daim is an IM client and library that supports many features, including add-ins, AIM proxy, buddy icons, chat, direct IM, file transfer, file sharing, send buddy list, and Trillian secureIM. It also supports retrieving News and Stocks, and scripting through Apache BSF. It also supports ICQ, can emulate Apple's iChat client, and supports iChat available messages as well.
licqweb is a Web frontend for licq. It interfaces with the Remote Management Service plugin and uses AJAX to provide real-time communication. It is useful for people who use IMs from multiple locations and want a 'centralised' application that means no more logging off and on, consolidates chat history to the one location, and prevents problems where messages are missed because another IM client received them.
sim (simple instant messaging) is an IRC client specialized for use with bitlbee. It is based on sic (http://suckless.org). It reads commands from standard input and prints all server output to standard output. It also multiplexes all channel traffic into one output, so you don't have to switch to different channel buffers. sim must be customized by editing its source code to insert the correct username, server, password, and identification information.
IM-Filter is a daemon that runs on a firewall and filters ICQ traffic. The daemon can identify file transfers, handle UIN and word blacklists, manage a list with currently logged in users, and log messages sent via the ICQ protocol. The modular design allows implementation of other protocols like MSN or IRC.