Pac-Man and Ghost
On December 30th 2010, my daughters Emily, Alicia, and Cara were playing a version of PAC-MAN on the Xbox 360. I immediately decided what I needed to do - I ran into the other room and quickly designed a PAC-MAN object in OpenSCAD and printed a few for the girls.
They immediately asked if we could make the Ghosts.. I said of course, showed them how OpenSCAD worked, and they told me exactly what to do to model the ghosts. We printed them immediately.
Here is video recorded back then of my daughters watching the ghost print:
http://www.youtube.com/watch?v=TYPVfw2tnLQ
The blog entry describing this is here (about 1/4 of the way down the page):