I miss it a lot. In Adobe Fireworks and Photoshop for example, you have this feature, which select any area in the image with similar pattern to that previously selected by the cropping tool.
An exemple of use is to select the Pink color of sprites and cut them off. In fireworks you simple press the magic wand tool on it and Alt + A + I to select all areas with the pink color, making easy edit of sprite sheets.
But it can go much ahead, making easy select similar colors and patterns in the image to edit them.