Styrofoam as an Art Form - Turning a cup inside out

I was just reading Diana Adams' Blog on artwork with a foam cup and a sharpie and was reminded of when I used to be very bored and would sit and very very carefully turn a styrofoam cup inside out.  It wasn't easy, and unfortunately I don't have any pictures, but it was time consuming.

I told my daughter about this the other night and she insisted I was kidding (which I do a lot) and that it was impossible.  Even after her mother confirmed the truth of what I was saying she still insisted it was impossible.  I guess it's time to do it again, except I no longer have time to kill and cups to waste.

I did find these references (now I know I'm not crazy):

Vimeo video of how to turn a styrofoam cup inside out
YouTube video
Blog for when you're bored