ICB has clients for Unix, VMS, and OS/2.
There are two Unix clients. The first is a compiled client that has many features, including readline command history, and tcl macro support. The second is an Emacs Lisp client which uses emacs environment features (including Emacs Lisp macros).
All of the clients except the VMS clients can be found on the new ICB ftp site ftp.sjsu.edu in the directory /pub/icb/clients. There is a manifest file describing each of the files in the clients directory. The standard unix tcl client, the Eric Lechner/Jon Luini forumnet client, the color icb client, the emacs client the zenicb emacs client and Mark Luljak's Curses based client are all there. The OS/2 client is also there, with links provided bellow.
There are two MS-Windows based clients being developed. One is being done in Visual-Basic by Michael Kirkham (mikeke/beek/grump/viktor). This one requires two files: vbrun200.dll and winicb.zip . There is a winicb homepage at: http://www.antfarm.org/winicb/.
The Other MS-Windows client is based on Win32, and is a full .exe file (no VBrun required). It is in the file wicb329B.zip. I've misplaced the info on who wrote this one, so if they could contact me, I would appreciate it.
Both the tcl and emacs clients can be retrieved via majordomo on the icb-programmers mailing-list.
The VMS Client can be retrieved via anonymous ftp from ftp.unm.edu in /pub/icb. (No link is provided here, since it is not given as a single archived file, but a collection of loose files).
The OS/2 client was written by Ed Boykin (Ham_Salad). You can download the source as a zip file (note, the source requires the IBM TCP/IP developers kit, which is a commercial product, so don't ask me nor Ed how to get it). You can also aquire the compiled version as a .exe file. Ed is still working on it. You can get more information by looking at his web page.
Both files are available via anonymous ftp from the ICB ftp site at: /pub/icb/clients/icbsrc.zip for the Source zipfile, /pub/icb/clients/icb2.exe for the compiled executable. Ed's comments on the project are also available.