documentr is a Web-based tool for editing and presenting software documentation. It allows you to easily maintain documentation for multiple products and product branches. Edits can easily be copied between branches, with merge conflicts being handled gracefully. It uses Markdown as its markup language, along with some extensions, and has a role-based permission system.
nimsg (the Network Instant MeSsenGer) is a compact, server-based chat program. Its features include the ability to chat with more than one person at the same time, the ability to post multiple times in a row, and the ability to let users choose their in-chat nicknames. It can be used as an alternative for IRC, for those times where you just want to have a small, local chat room.