Pirates are a frequent topic in fiction and are associated with certain stereotypical manners of speaking and dress, some of them wholly fictional. Some inventions of pirate culture such as "walking the plank" were popularized by J. M. Barrie's novel, Peter Pan, where Captain Hook's pirates helped define the fictional pirate archetype. Robert Newton's portrayal of Long John Silver in Disney's 1950 film adaptation of Treasure Island also helped define the modern rendition of a pirate. The recent Pirates of the Caribbean films have helped kindle modern interest in piracy and have succeeded quite handsomely in box office grosses.
The classic Gilbert and Sullivan operetta The Pirates of Penzance focuses on the Pirate King and his hopeless band of pirates on the South coast of England. The Pirate King is often believed to be inspiration for Jack Sparrow (Johnny Depp's character in Pirates of the Caribbean). Various variants on the pirate idea exist, notably "space pirates" in science fiction, such as the TV series "Firefly," that imagine future space shipping subject to similar pressures as shipping in the Age of Exploration. Pirates are also common mascots and names of sports teams.
While pirates are generally terrible people, folklore has romanticized them (as with other similar figures drawing on the "bad man with a heart of gold" theme). Some pirates are even protrayed in a Robin Hood-type manner, which is not as far-fetched as it may sound since he was basically a land pirate. We don't know whether pirates would beat ninjas in a battle (ninjas are pretty cool, too), but the thought of a bunch of wild dandies sailing the lonely seas in search of adventure and gold is pretty intriguing.