Check out this article, Living NOAA's Second Life
It is about how the National Oceanic and Atmospheric Administration (NOAA)--a government agency--is using a virtual world to reach into the future and it has some great advice on considerations before launching into a virtual world.
My advice to other federal agencies interested in virtual worlds is to define your goals before you break ground. Use the numbers in terms of visitors, time spent on the site, etc., to help refine your design and improve your conversion rate to your goal.
Start small by focusing on a topic that is of interest to local management. Wow a manager with an easily understandable and relatively cheap application. Don't be shy about asking questions and fostering a sense of community development...as described by Eric Hackathorn who is, among other things, co-chairman of the Metrics and Research Working Group at the Federal Consortium for Virtual Worlds
They are also working on some forward thinking applications for virtual worlds and data sets.
One recent prototype we call Second Earth attempted to blend the capabilities of tools like Google Earth or Microsoft Virtual Earth with the collaborative capabilities of Second Life. You can fly through and remotely collaborate about a real-time dataset.
Some resources and articles on the topic:
NOAA Comes to Second Life
A New Wave of Learning
Meteora (SLURL Link to NOAA island)
(SLURL Link to NOAA island)
If you haven't checked out NOAA's island in Second Life, you really need to have a visit.
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