Hubl.in is a free and open source video conference solution.
HumHub is a free social network software and framework built to give you the tools to make teamwork easy and successful.
Self-hosted chat for small teams that ships with killer features such as LDAP/Kerberos authentication, a REST-like API and XMPP support.
Mastodon is a free, open-source social network.
An easy to use multi-channel webchat solution for small and large groups.
Mumble is a low-latency voice chat software that provides excellent audio quality and is perfect for gaming.
Openfire is an efficient and lightweight real time collaboration server that helps you to build your own IM network.
RainLoop Webmail is simple, modern and fast email solution.
Prepare to take off with the ultimate chat platform and experience the next level of team communications
Roundcube is a webmail solution with an application-like user inteface that's easy to install and configure.
A powerful open source group chat software.