Poking around http://www.flickr.com just now, I came across somebody doing a project that I had planned to do. And doing it well. He's taking a collection of pictures sharing a keyword ("eye" in this example, he does several others), and averages them together.
Very well done.
If that floats your boat, this will positively propel your kayak: http://www.salavon.com/HomesforSale/HomesforSale.shtml