BigScreen VR - Your desktop in virtual reality, with friends; play games, watch movies, and hangout in VR.
VeeR VR - Global VR video community
VRidge - Play PC VR games inside your mobile VR headset.
WebVR Experiments by Google - Easily build and share VR experiences on the web!
Virtual Desktop - Use your computer in VR
AIFE for Virtual Reality - Launch a Virtual Reality experience (and more) in 60 seconds