Now I remember why I rarely go to the movies.
POTC (the first part) was a rather amusing film. But POTC2 was a lame sequel (like they usually are), and POTC3 was trash (like they usually are, see Terminator III). POTC3 takes long and is boring. It is impossible to follow the complex story line. Some scenes have awesome effects, like the world going upside down at sunset. But then there are only weird scenes, like the slapstick marriage during a saber battle. Not recommended, not even as a popcorn movie.