Riverrock, what I do is to get the maps on CD, print out the route of any particular flight, and carry a separate map covering a larger area for major diversions. This gives me a throwaway map printed on ordinary paper that is easier to handle in flight. I hang a biro on a string round my neck and can scribble away as much as I like. If I want to write down a clearance or whatever I have an A5 kneepad strapped to my leg with the plog. Anything more, turn the map over and use the back. The kneepad provides the necessary hard surface.