I use a bag/soft case that is used for holding rubber fishing worms. It is first aid red and a bit of careful cutting took the manufacturers patch off. The zip seal bags they use are clear and very tough. They are also non-reactive bags, so if something leaks it won't eat through.
http://www.anglersupply.com/product.cfm?model=Worm%20Wrap&manufacturer=Tackle%20Logic&type=Tackle%20Storage%20%26%20Cases

I have several of them. 2 of the larger (shown in the link) for the house and truck, and a smaller one that is 8"x6" for my pack/BOB. I've had them for 5 or 6 years now, and they have been very durable. (the one in the link shows manufactures bags in the case, they come with clear empty bags)

It zips open completely and you can page through to find exactly what you want, like a notebook. I have an amazing amount of stuff neatly organized and easy to find. It came with extra adhesive tabs, so you can stick them on your own zip seal bags and put them in the binder rings. You can also buy extra bags. I can highly recommend this bag, it has been perfect for me. (I bought mine in a local sporting goods store.)