Social Networks
Notes

If you have system administration knowledge, please strongly consider running an instance of pump.io (or something else) for your friends, family, or favorite community. Many of them would be willing and grateful to escape Facebook if you provide them a way out.

For those of you without your own server, RetroShare is the easiest way to start your own encrypted social network.

identi.ca is a popular Twitter-like social networking hub for the free and open source software community runs a pump.io software platform.

Proprietary
Facebook
Google+
LinkedIn
Twitter