Second Life - Second Life is a virtual reality platform where individuals interact in a virtual world. The software was developed in 2003 by Linden Labs. More than one million people now regularly use the software.
Gather Town - Spatial video-chat worlds for work and play
Vircadia - Vircadia is an open-source and decentralized real-time VR creation platform for university, enterprise, social, and OpenSim users.
SpatialChat - Virtual space platform to help remote teams collaborate.
VRChat - Create and play in virtual worlds with others
Teamflow - Feel like a team again with your own virtual office