I am alone on a small island that is about the size of a roundabout in the middle of a vast ocean. With my ghostly body I look up at the night sky and contemplate what to do next. Maybe I will make the sun rise, build some more land or just read some more of the wiki. I've just installed OpenSimulator (a.k.a. OpenSim), a "3D Application Server". What this means is that it can be used to host "virtual worlds", a bit like SecondLife. In fact you can use the SecondLife Viewer as a client for it. After hearing about at various points for quite a while and finding a really good set of instructions on how to set it up, I couldn't resist having a go, even though creating virtual worlds is a bit of an excursion for me.