Open Source Virtual Worlds

Just compiling some info about open source virtual worlds. Hm, in general, from research thus far, it seems that vworld stuff focuses mostly on back-end persistance tools and very little on creating actual spaces (other than ralph kostner's effort, which looks like the clear winner at this point - but even it is very 3d worldy - haven't seen any examples of a vworld that is more practical and businessy...)

Asbahr.com
http://www.asbahr.com/beyond.html
Beyond2 open source virtual world framework
Looks very teccy gamey
Based on python. Looks like a one person project.

Metaverse Project
http://metaverse.sourceforge.net/
The server engine can be installed, configured and administered by anyone to create their own metaverse, somewhat analogous to an Apache web server for web content. Instead of web pages, a metaverse server will serve up the data and contents of a 3-D virtual world that can be customized by the administrator. Very interesting... still requires user to download a client though.

Second Life
Has opened it's viewer application ~ Jan 2007.
Wiki: http://wiki.secondlife.com/wiki/Open_Source_Portal
FAQ: http://secondlifegrid.net/programs/open_source/faq

Dutch Pipe
http://dutchpipe.org/
About: http://ajaxian.com/archives/dutch-pipe-open-source-avatarchatvirtual-world-php-framework
Avatar Demo: http://dutchpipe.org/test.html
With DutchPIPE open source software, web developers can make virtual multi-user environments. Each web page becomes an abstracted environment or location where visitors and other items on the page are visualized. This status is retained as visitors move around. A lot of real-time interaction is possible. The result: Persistent Interactive Page Environments. DutchPIPE uses AJAX and the DOM for the browser - it works without Java, Flash, plug-in or firewall adjustments. On the server, PHP 5 is used.