I've got a digital mapping system, based on OS Landrangers, installed on my PC - one on which you can highlight your route, print out a route profile, etc. It's a very useful piece of software, not least because it means not having to carry large numbers of maps on longish trips. However, on a previous trip, while changing the map printout over to the next page in the pouring rain, the map got wet and the ink ran. I could still read things without too much problem but it got me thinking: what's the best way of overcoming this? Waterproof paper? Waterproof spray on solution? Plastic laminates?