And a couple more that I forgot:
The auditorium at my high school was supposedly haunted, too. It has catwalks way up in the attic around the ductwork. Back when it was built, a janitor fell off one of them, into a ventilation shaft and died. Members of the drama department insisted that the place was haunted and had stories about what went on late at night. My fellow band geeks and I also spent a lot of time in there, but never saw anything. I did, however, get a chance to thoroughly explore the building and got into all the "restricted" areas. The catwalks were terrifying, but still not enough to deter a pack of teenagers.
When I lived out in the middle of nowhere, the firm I was at had some files at another building, which was a defunct law firm in a late 19th century building. It hadn't been updated in decades and the upper floor was a dusty, creepy and ancient fileroom. Supposedly, it was haunted and late at night, you were supposed to hear footsteps pacing the hallway. One of the secretaries was completely freaked out by the place and refused to go there alone.
There was a key at the office, so some friends and I slipped in there at night a handful of times. Great fun after a few drinks. It was creepy, but none of us saw anything.
Which reminds me, I need to ask the owner of the bar I hang at if there are any ghost stories. The building was built in the late 1890s and I know that three people were killed inside. Back about 20 years ago, three people tried to hold it up and started collecting the patrons' wallets. Unfortunately for them, there were two off duty police officers inside. They opened fire. Two robbers died inside and the third staggered out and died on the sidewalk. The bar's owner decided to leave the bulletholes in the walls and you can see them today. I don't know if there are any ghost stories there, but maybe we'll start some.
Also, I've meant to take one of the ghost tours of the Queen Mary in Long Beach. They offer them periodically and they supposedly take you into the bowels of the ship.
Despite being a skeptic, I love the folklore and mythology of ghosts and other paranormal activity. Probably a bunch of nothing, but still a lot of fun. It also ties in with my love for old buildings and the various odd corners of the world.