Fascinating visualization of the US airspace:

"FACET is a computer program developed by NASA that generates simulations for managing air traffic scenarios. It provides a "big picture" view of what's happening in the skies overhead. For any given moment in time, it can show thousands of aircraft swarming through our national airspace. With each aircraft represented as a tiny icon, a FACET simulation can look like an "ant farm in the sky," with aircraft clustering around major airports like ants targeting a drop of peanut butter."

<http://www.nasa.gov/topics/aeronautics/features/big_picture_facet.html>

Might be some good inspiration for all you particle jockeys out there.