BOINC - BOINC is an open-source software platform for computing using volunteered resources
Qwasap - A Telegram bot that lets you talk to people who are located anywhere in the world.
Apache Mesos - Apache Mesos abstracts resources away from machines, enabling fault-tolerant and elastic distributed systems to easily be built and run effectively.
Jodel - What is Jodel all about? Jodel is the community that shows you what's happening in your area in real-time.
JPPF - The open source grid computing solution.
Treadie - Create your own micro-social network for topics