A role-playing and miniatures set of rules for the golden age of pirates, privateers, and the Royal Navy, boarding and duelling rules included.
From the Wikipedia entry:
Buccaneer is a concise 16-page book of rules for playing pirate characters in the 17th and 18th centuries. It was designed by Carl Smith and published by Adversary Games in 1979. The rules cover character types, progression, duels, boarding actions, and plunder. Combat rules cover blade, gun, and cannon combat.