Immersive Systems, Inc. Home of Meme: extensible networked virtual reality software. http://www.immersive.com/

Activeworlds 3D virtual reality chat plugin software and servers. Design worlds, chat with friends, play games. http://www.activeworlds.com/

OzGate A site running several DigitalSpace Traveler worlds. http://www.OzGate.com

Atmosphere Infopool Adobe Atmosphere resources: tutorials, tips, galleries of worlds, avatars, scripts, objects, and sounds. In German and English. http://www.atmoinfopool.com/

Dive An Internet-based distributed multi-user VR system, developed by researchers at the Swedish Institute of Computer Science since 1991. http://www.sics.se/dive/

Lucidspace 3D Community A collection of multiuser VRML worlds (requires IE with Blaxxun Contact plugin) and forums. http://www.lucidspace.com

Contact Consortium A research and trade association for virtual worlds, avatars, virtual community. Organizer of yearly Avatars conference. http://www.ccon.org

Cybertown A popular and long-running web-based multiuser world, using VRML and Blaxxun browser software. Chat, and use objects. http://www.cybertown.com/

Virtual Object System / Internet Virtual Reality A software infrastructure for distributed object-oriented programming. The primary application for VOS is a multiuser virtual environment run by many interconnected clients. http://interreality.org

Shared VR Wiki at VRSource A collaborativly-built website about shared VR technology and software development (part of VRSource.org news site) http://www.vrsource.org/TWiki/bin/view/SharedVR/WebHome

Goonietown A Blaxxun Contact-based 3D multi-user chat community. Users can create worlds or hold a community job. http://www.goonietown.com

DigitalSpace Corporation Software and world development company. Also home to Traveler online community. http://www.digitalspace.com/

VRMLWorld.net A portal to various VRML worlds, with multiuser chatting via VNet+. Free to use and to add your own worlds. Works best with IE and Blaxxun Contact. http://vrmlworld.net/

Moove 3D chat world. Customizable avatars with facial expression. Users can chat, build and furnish a house, listen to music, share files. Can be integrated with external tools. http://www.moove.com/

Alterlinks Active Worlds resource for visiting or creating your own virtual world: hosting, textures, 3D objects, avatars, skyboxes, tutorials. http://www.alterlinks.com

Virtual Worlds Review A guide to online virtual worlds with a focus on social interaction. Basic info, visitor ratings, reviews and helpful links for each program. http://www.virtualworldsreview.com/

Second Life An online society within a 3D world where you can explore, build, socialize, and participate in their own economy. http://secondlife.com/

Dreamland Park Explore, chat, and build a community using Active Worlds software. http://www.dreamlandpark.com

Spid3r Technologies A producer of interactive 3D communities using their own patented technology. http://www.spid3rnet.com

VRSpace An open source (gpl) virtual reality cross-platform 3D community software. http://www.vrspace.org/