When I was in California (where else?) I bought a Buddha Board. Here’s the description:
“Buddha Board is based on the Zen concept of living in the moment. You simply paint on the surface with water and your creation will come to life in bold design. Then, as the water slowly evaporates, your art will magically disappear leaving you with a clean slate and a clear mind – ready to create a whole new masterpiece. Allow yourself to ‘let go’ and not be concerned with each outcome – live for the moment and enjoy!”
Goal-free and fun!