While browsing the map section in my local REI recently, I ran across this cool product: AquaSeal Map Seal. Map Seal is a high-polymer coating that you can brush onto your maps to provide a permanent waterproof coating that will not be compromised by repeated folding and unfolding. While I prefer to purchase trail maps that are already waterproofed and durable (such as printed on Tyvek), this is a great alternative when such maps are not available.
Map Seal comes in two sizes: a 4-ounce dauber container, or an 8-ounce bottle with sponge brush applicator. With an MSRP of $12 for the 8-ounce container, it’s a pretty good deal—one bottle can reinforce up to eight maps.
The only downside to this product is that it will not work with maps printed on an ink-jet printer, as the ink will run during the coating process. Check back soon—we’ll be testing this product to see how it performs in the field!

[...] month we featured AquaSeal Map Seal as one of our ‘cool products.’ We finally had the chance to try it out and have to say that it definitely holds up to its’ [...]