I'm sure some of you may have seen or used this site before, but Multicolr Search Lab (not a misspelling) is such a simple and cool use of the Flickr API, that I had to share it.
By clicking on a color swatch you see 50 matching Flickr pics. Great for building your own photomosaic. Even cooler is the fact that it modifies the link string so that you can bookmark your color combinations and come back to them later. With nine gradient shades of each color, the combinations a numerous.
Hope you dig messing around with this as much as I do.