icbm (extensible threaded ICB client in Perl)

ICB (Internet CB) is a teleconferencing system that allows Internet
users to participate in realtime online discussions (similar to IRC).

ICBM is a threaded ICB client written in Perl5 which supports a
superset of the functionality of CICB (the ICB C Client, the de facto
standard ICB client). This allows ICBM to be readily extended to
support many features that CICB does not, and to gracefully do a
number of things that CICB does poorly if at all.

Note: in some terminals (e.g. urxvt), when icbm exits, it will
leave the terminal in a state where the backspace key prints "^?"
rather than backspacing. You can fix this with "stty erase ^?".
Other terminals (e.g. xterm) don't have this problem.