How about a flotation helmet with heads up display.

"Parallax" wrote in message
om...
| Looking at a chartplotter and a 3d mapping program gave me some ideas.
|
| Build a small computer display into the lenses of glasses. Wherever
| you looked, they could either be transparent or display the positions
| of buoys, etc and water depth contours superimposed on what you were
| looking at.