xIrc is a QT based IRC client featuring individual windows for each conversation, channel member lists, full DCC chat capability, DCC file get and send capability, a subset of the standard IrcII commands, many with simplified interfaces, automatic ban mask generation for easy and reliable banning, notification lists, ignore lists, mIrc colors, optional CTCP2 protocol (except fonts), and full documentaion in ASCII and PostScript.
xtell allows you to send messages between computers running xtell server. It is easy to use in scripts (i.e. to notify you when you get a mail or something else happens) or as a network-aware replacement for write(1). It was originally based on Michael Bacarella's ident2 server and Jozef Knepp's VMS implementation.
Xws is a text mode multi-player crossword and chat server. It presents the same puzzle to everyone, allowing people the option to try and/or discuss solutions. Play may be friendly collaboration or fierce competition, depending on the players' dispositions. Xws supports hundreds of puzzles in the popular Across Lite file format. Copyright issues prevent the distribution from including any puzzles, but several archives and resources are listed in the README.
NullLogic Groupware is a modular Web-based groupware and email system designed for contact management and event scheduling. Additional features include private messaging, public discussion forums, webmail, shared bookmarks, file sharing, call tracking, order processing, an XML-RPC API, and integrated POP3 and SMTP servers.