Cactus Comments is a federated comment system for the web, based on the Matrix protocol.

“Zulip combines the immediacy of real-time chat with an email threading model. With Zulip, you can catch up on important conversations while ignoring irrelevant ones.”

Secure, fully featured, and completely free video conferencing

Go ahead, video chat with the whole team. In fact, invite everyone you know. Jitsi Meet is a fully encrypted, 100% open source video conferencing solution that you can use all day, every day, for free — with no account needed.

Matrix: Fully distributed persistent chatrooms with no single points of control or failure #chat -

Jede bei 1und1 gehostete Emailadresse ist gleichzeitig ein Jabber-Account. Macht über 5 Mio. neue Jabber-Nutzer. Cool :)