I remember in highschool or was it college when I saw a poster that was a grid of photos that made up a larger picture and I was floored. It was back in 93 and at the time it blew my mind. Ever since then computers have made it easier and easier to do this type of grid work. I have been experimenting lately with it myself doing abstract grids. I am going to continue to do so. You know watching shows like Georgetown cupcake you can see how this has become a go to method for artists now a days. They do most of their cupcake layouts this way. My uncle sent me these great photos today that was done with coffee. AWESOME.