I first discovered the world of ACEOs (Art Cards Editions & Originals) about four years ago. These tiny little painting can be any medium or material as long as they are the size of a trading card 2.5" X 3.5". They are also called ATC (Art Trading Card) or Sketch Cards. The popularity of these mini paintings has exploded over the last few years. Mine are all painted on premium watercolor paper using the finest Winsor & Newton paints. I have sold hundreds of them, my lighthouse series being among the most popular.