OpenSimulator, the free and open source 3D application server program used to create virtual environments.
Justin Clark-Casey is a core developer on the OpenSimulator.org project. A long time FLOSS user, OpenSimulator is his first project to which he has dedicated large contributions. He has been working as a core developer on the project for over a year and a half.
He is also a lead developer for Black Dress Technology, a startup that uses OpenSim technology as part of a solution for product and fashion design.