Crumpled City Maps by Emanuele Pizzolorusso solve the problem of folding up a map wrong by making it crumpled to start with. Twenty-three cities are available and made of a waterproof material. Available at palomar for €12,00 in the EU or on Amazon for $10-30 in the US.
Poketo! Travel Journal has space for notes, as well as a pocket for keeping loose papers at bay. I'm always picking up flyers to jog my memory later and like to having important information close at hand. Available from Poketo for $24.