In google earth you can do image overlays. So, for example, you can take screenshots out of topozone.com and overlay them with map data. A great example is if you take a shot from topozone of Mildred Island and lay it over the Delta map ;) If they had that on a meter, that would be totally cool.

Another one I was thinking of this week was with those Fish-n-maps that offer GPS coordinates. Fish-n-map company should make it so if you buy one of the paper maps you can also go to their web site and download all of the coordinates as a file for a Lowrance or Humminbird. I was thinking of programming in some of the coords the other day but it's such a pain. A file would be cool.