Ask HN: Which self-hosted solutions are you using?

I came across Perkeep[1] project today. I know some other self-hosted solutions like Rocket chat[2](Slack alternative), Redmine[3](Project management) etc. Curious what other self-hosted are there and which one you are using?

[1]: https://github.com/perkeep/perkeep

[2]: https://github.com/RocketChat/Rocket.Chat

[3]: http://www.redmine.org/