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
Blog for when you're bored