I may be way out of my depth here, but I used to have a fairly extensive series of constructions in Active Worlds--still there I suppose. Finally got tired of paying every year and no one else could come and see anything without joining. Anyhow, I was just wondering if there's any software available that would allow the creation of such a 3D space (though obviously much smaller) that could be easily accessed by anyone with a freely available program or plugin of some sort. I like the idea of standard parts used at Active Worlds, so that building a construction would be a matter of duplicating and moving standard units--wall, floors, trees, whatever. The primary necessity is to be able to travel THRU the world. I am not looking for just 3D rendering of flat images. Anyone have any experience with such 3D spaces and want to share a few hints?