Fishfinder + Mac (or iPod Touch)

Has anybody ever tried pulling in data from a fishfinder and graphing the data via processing?

I have access to an older fish finder (Humminbird 110) and I'm interested to see if I could use my computer or ipod touch to display a more interesting graph (color...as the fishfinder comes with a greyscale display).

From what I've read this seems functionally similar to the Ping example...anybody try something like this before?

Cheers,
Mike