It is called Graffix Rub-Onz. You print your design (in reverse) onto a sheet of plastic. Then attach an adhesive to it and then attach to your surface by rubbing it on. It was very simple to use. Due to the transparency of the printer ink on the plastic, I chose shades of brown for the various parts of the design and was pleased to find it came out looking like different shades of stain.
Here's the product website: http://www.grafixarts.com/product/RubOnz_Transfer_Film_
Since taking that picture, I've actually changed the top designs a little. Thats another great thing about this product, it peels/cleans off really easy. I'm sure its ability to do that depends on the surface you put it on, but with polyurethaned wood, it cleaned off easily.