Thank you, David, for the link to Virtual World Framework as this
interesting new Ruby / Javascript offshoot of Croquet had passed me
by. You wrote:

> Nikolay Suslov also had a very nice version which I don't have a link for
> right now.

I think you mean Krestianstvo SDK. Though I didn't use it myself, I
watched some very nice video demos of its Kinect motion sensing
feature.

The krestianstvo.org website has a parking page right now.

However the images are still available:

https://code.google.com/p/krestianstvo/downloads/list

as is Nikolay's blog:

http://nsuslovi.blogspot.co.uk

Have fun! David