The slot held a few hundred bucks' worth of last week's folding paper.
"I can assure you it's not the sounds of people folding paper," he replied, laughing.
The Japanese are clearly the masters of origami, the art of folding paper, but they are not alone.
Well, don't look now, but there's a new wrinkle to the old Japanese art of folding paper.
But who first decided that folding paper into elaborate shapes sounded like fun?
Sang-eun is a pretty 20 year old girl, that is warm hearted and possess an extraordinary gift for folding paper into various figures.
Well that looks similar to Peter Callesen, a danish artist that makes sculptures just folding paper.
He began folding paper when he was 3 and started designing his own origami models during childhood.
He was adept in folding paper into different shapes.
Origami may also be used to construct the cube root of two by folding paper.