Could the world someday just share one distributed OS?

Croquet is a combination of computer software and network architecture that supports deep collaboration and resource sharing among large numbers of users within the context of a large-scale distributed information system. Along with its ability to deliver compelling 3D visualization and simulations, the Croquet system’s components are designed with a focus on enabling massively multi-user peer-to-peer collaboration and communication.

and from the FAQ:

The Croquet project is an effort to develop a new open source computer operating system built from the ground up to enable deep collaboration between teams of users. To do this, the project seeks to define and develop a system is focused on the simulation and communication of complex ideas. We call this “communication enhancement” - the direct extension of the abilities of humans to develop, understand, and describe even the most complex simulations. Croquet enables this communication by acting as the equivalent of a broadband conferencing system built on top of a 3D user interface and a peer-to-peer network architecture.

The site includes whitepapers by David Reed, Alan Kay, David Smith, and Andreas Raab