One of my favorite projects/trends right now (besides Google Earth/Maps, GeoWeb, MoSoSo, Web 2.0) is probably called Croquet. Perhaps it is the ultimate culmination of all my other favorite trends/projects into one single project. Sounds very promising to me.
"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. Social computing like Croquet involves systems that support the gathering, representation, processing, and dissemination of information that is distributed across many individuals. Such systems include collaborative filtering and recommender systems (e.g., firefly), online auction sites (e.g., ebay), and open source virtual communities (e.g., slashdot). Social computing systems are likely to contain components that support and represent social constructs such as identity, reputation, trust, accountability, presence, social roles, and ownership. In such systems, it is not just the data that matters, but who that data "belongs to", and how the identity of the "owner" of that data is related to other identities in the system."