Instant Messaging

• AOL Instant Messenger
  • gaim
    GTK based AIM client
  • LAIM
    ncurses based AIM client
  • naim
    ncurses based AIM client
  • nak's laim
    AIM client based on LAIM
  • TiK
    Tcl/Tk 8.0 version of AIM
• ICQ
  • cicq
  • GICQ
    GTK-based ICQ clone
  • GtkICQ
    GTK-based ICQ clone
  • ICQ
    The popular "instant message" software for Java
  • kicq
    KDE/Qt based ICQ clone
  • KXicq
    KDE/Qt based ICQ clone
  • Licq/KDE
    Qt based ICQ clone with additions for KDE (based on Licq, who's homepage is 404...)
  • micq
  • nicq
    GTK based ICQ clone
• GNU Talk
• GTKYahoo
  GTK based Yahoo pager
• Jabber
  An instant messenger like ICQ or AIM and it also works with both of them
• LinPopUp
  GTK-based enhanced port of Winpopup for Samba networks

IRC

• Clients
  • cIRCus
    IRC client for Linux/X11
  • EPIC
    Enhanced Programmable ircII Client
  • irssi
    GTK+/GNOME IRC client
  • KSirc
    sirc based IRC client for KDE
  • sirc
    Perl based IRC client
    • ircspeak.pl
      IRC text to speech for sirc using the Festival speech synthesis system
  • Sula
    IRC client for X
  • X-Chat
    A GTK (and optionally GNOME) based IRC client for X
  • Zircon
    Tcl/Tk based IRC client for X
• Servers
  • The Perl IRC Daemon

Miscellaneous

• HCP (Human Communications Protocol)
  A protocol for text, audio, and video communication, and it's Java implimentation (client and server software)
• Q-SeeMe
  A CU-SeeMe compatible videoconferencing client for Linux that supports send/receive video, audio, and chat