Dan Burns explains his space-time warping demo at a PTSOS workshop at Los Gatos High School, on March 10, 2012. Thanks to Shannon Range from the Gravity Probe B program for creating the original demonstration which he shared with Dan in 2004.
Information on how to make your own Spacetime Simulator can be found here:
http://prettygoodphysics.wikispaces.com/PGP-Modern+Physics
