An origami coaster with a pattern of leaves. After designing, I found out others had done the same before, for example you can check out this picture [update: link is dead] by Marcia Shintate. Not surprising, given this model’s simplicity.
Very strong creasing (in my case combined with wet folding) is required on the edges if you want to prevent this model from opening by itself in the center. Alternatively, you can just use the weight of the object (such as the brass hedgehog paperweight I used here) placed on the coaster to keep the model in shape. This model can be used as a tato (albeit with a very weak lock) since there is a pocket below the leaves with room to hold a flat object such as a piece of paper.