My friend and I were talking about the new SI depthfinders and the 3D imaging and he had what I thought was a cool idea. It may already be possible and we're just slow. Have the DF be able to record all bottom contour including trees and what nots using GPS coordinates for locations of your trip and then be able to down load it to the computer and then a program write it back permantly to the 3D program on your card. I thought that would be awesome but, of course we don't know squat about computer programming so it may be impossible.