In the context of my masters project 2014, our team completely re-implemented the InstantLab platform.
The InstantLab platform is a middleware that enables Web sites (and their users) to easily run operating-system experiments in the cloud. It therefore provides an unified Web API to other Web sites while using the resources of various infrastructure as a service (IaaS) providers. Those providers include Amazon Web services, OpenStack, CloudSystem 7.2 HP Helion and more.
My contributions included software design (esp. architecture and data modeling), integration, being the Scrum master and - of course - implementation.
Besides a Web-front end and OpenID authentication, the main focus was a module for network port forwarding. It is used to overcome NAT barriers and thereby use private clouds publicly in a controlled and secure manner. Since sockets are bound to operating system processes, a mentionable feature is the ability to control forwardings across processes and even application restarts.