Still on a nautical theme and still being inventive with "paper" (and granted with graceful permission to photocopy ship pages for personal use), being a much cheaper entry point into a wargaming period than metals or even plastics for that matter, plus some simple wargame rules (see below):
I must confess this was something of an "impulse purchase" while doing a more boring Amazon book purchase. I wonder how much "Amazon trade" is generated this way ;)