Ok.. this isn't from a sketchbook, but I wanted to post anyway. Cinta Vidal is a spanish illustrator, these pieces are on wood and can be rotated 360 degrees (perhaps a bit of a gimmick, but interesting). I particularly love the containment of these works.. the complete in tact feeling and weight(less) of each little world that is rendered. Enjoy. For more of his paintings, illustrations and commercial work, go here.