I discovered a fun piece of third-party software at flickr.com. A search feature called "retrievr" allows users to search for photographs by making simple lines and dots. It retrieves photographs that have similar colors and patterns. Thus, a diagonal line drawn across the box led to images in which which a shadow or a model's hair fell at a similar angle. It was interesting to see how this non-verbal search engine worked. I can imagine using it if I were making a collage or choosing a photo to fit into an existing color scheme.