How about a feature on ships to raise a friendly "White Flag", or a hostile black skull and xbones "Pirate Flag". Like they did in olden pirate days. :)
So you fly the white flag, that lets other white flags know you are friendly, and want to work together. The catch, White flags can't hurt other white flags. A Black Flag comes in with his pirate flag waving high above the crows nest, you know they have hostile intentions. Man the canons! Avast ye land lubbers!
Say you joined forces with another white flag; and you believe the time has come to betray them and steal their booty. You must lower your white flag, and raise the black! While you are raising/lowering flags, A warning is sounded and your ship is somehow identified visually. Sort of like how a skullfort is identified. Say flag raising/lowering takes 30 seconds. Your "allies" have time to react and aren't screwed.
I think this might be a way for pirates to work together. As an added bonus, this is somewhat historically accurate. Thoughts?
