Cachet : Beautiful & simple service statuses. The open source status page system, for everyone.
Zulip : Powerful slack-like open source group chat
Riot : Riot allows teams to communicate across a wide range of collaboration apps. If some team members use Riot while others use IRC, Slack or Gitter, Riot ...
Beehive : Beehive is an event and agent system, which allows you to create your own agents that perform automated tasks triggered by events and filters. It is m...
ProjectPier.org : ProjectPier is a Free, Open-Source, PHP application for managing tasks, projects and teams through an intuitive web interface. It must be downloaded a...
Astuto is a free, open source, self-hosted customer feedback tool. It helps you collect, manage and prioritize feedback from your users.