Avatars traveling between the 3D web and virtual worlds.
The inDuality client is embedded in a Web page using standard HTML. The client determines the type of content to be rendered, checks to see if the needed files have been installed to support the content, and that they are up to date. The user then interacts with the virtual world in the same manner as they would through the original client.
I watched Peter give a demonstration where his avatar moved in-between virtual worlds by moving closer to the pillars in the plaza pictured above. Each pillar is an entry point to a virtual world. The transition from world to world was seamless (minus the loading screens). It is hard to say whether inDuality is just a "client of bundled clients", but again a cool concept for traveling between multiple worlds.
A quick interview with Peter Finn at the Virtual Worlds Expo 2007.