Singaporean artists Jenn Perng and Ink Julep teamed up to elaborate these interactive and full of imagination postcards. Indeed, the users have to complete these partial drawings with the coffee stain their cup left on the paper. This drawing project titled PostCups is available on this website and each lot bought contains 7 watercolors including a panda, a bicycle, a boy with a balloon or a cat. In other words, here is a perfect way to spend a much more entertaining coffee break.