After coming across Second Life, it took me a while of research to learn of this already more than 10 year old hype of internet technology.
I was researching for developing a virtual tour online for Biblical materials such as the Tabernacle, Solomon's Temple, etc. Apparently these things are lacking, while the secular materials are plenty in this area.
For me, it's not easy search to finally come to know the term: Open Sims. Similar to Second Life, only that it is free. Open server, everything self-achievable.
Although, during the search, I have come across this "Unity3D", another very well graphic oriented web-based 3D virtuality, which is supposed to work with Adobe's SmartFox Server. Giving an all browser user friendly environment.
I would choose to start with Unity3D, but perhaps I should briefly look into this Open Sims so as to not be a frog in a well.