VRChat - Create and play in virtual worlds with others
Plexamp - A small music player with a number of unique features
Vircadia - Vircadia is an open-source and decentralized real-time VR creation platform for university, enterprise, social, and OpenSim users.
Headset - Personal music player for Youtube and Reddit
XSight - Find friends and places in AR using your phone camera
Poolsuite™ - The super-summer music player