BOINC - BOINC is an open-source software platform for computing using volunteered resources
Winaero Tweaker - Universal tweaker software which supports Windows 7, Windows 8, and Windows 8.1.
Apache Mesos - Apache Mesos abstracts resources away from machines, enabling fault-tolerant and elastic distributed systems to easily be built and run effectively.
Ultimate Windows Tweaker - Ultimate Windows Tweaker is a freeware Tweak UI Utility for tweaking and optimizing Windows.
JPPF - The open source grid computing solution.
GIGATweaker - GIGATweaker is a powerfull and compact application that allows you to optimize and tweak your OS.