For Your Astronomers: Orbit Viewer [Google Chrome Experiment]
Link: Orbit Viewer
A sort of "Where are they now" for spacecraft & comets: Check out real-time positions, along with historical and projected flight paths of our solar system's trailblazing spacecraft and comets. All in a zoomable/rotatable 3D interface. Using historical and real-time trajectory information for NASA's JPL Horizons system, and in-browser WebGL & Three.js rendering.