- tkabber http://tkabber.jabber.ru/
- tkchat (I guess)
- [Pidgen] (formerly [GAIM]) has a Tcl extension mechanism ( http://developer.pidgin.im/doxygen/dev/html/tcl-howto.html )
- tik
- tac
- [ccmsn] http://msn.compucreations.com/
- [MiniTik] http://sourceforge.net/projects/minitik/
- Coccinella http://thecoccinella.org/
- JiMM
- dirc
- aMSN
- XChat
- BitchX-73 http://www.bitchx.com/
- [cIRCus]
- [keirc] http://tedi.heriyanto.net/keirc/index.html
- [OpenVerse Visual Chatz] (maybe)