To me, some of the most interesting tanks were the ones that performed the worst in battle, mostly German and British. The German tanks at the beginning of the war were not especially battle worthy and they lost a relatively high percentage in the invasion of Poland.
I mentioned the Japanese clip fed light machine gun. A similiar idea is how a M249 machine gun will take a standard M16 magazine. Again I suppose it was a good idea but I've been told they really are not reliable that way.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
Buy War Bonds.