During my college years, I found out that most dorms in my University were haunted in one way or another (as stated in my other submissions). One dorm in particular stands out because it used to be a hospital. To this day, a nurse's station greets visitors at the entrance, while the double doors leading out from the hallway are made to open to the left and right.
A friend of mine was staying there, and in the middle of the semester started saying that she was going to move out. When I asked her why, she said that several nights for the past few weeks, all of the girls in the room (herself included) would all wake up at the same time in the middle of the night, at 3:00 AM. Her roommates would also swap stories about seeing a shadowy figure at their window at night. The figure never moved, just stayed there, arms crossed and looking in on them.
Another friend in another dorm on campus kept telling us stories about how someone always knocked on the door of their room in the middle of the night. Three sharp knocks, no more, no less. And every time they opened the door, there would be no one outside or even in the hallway.
This friend also freaked out because once, she went home for the weekend. When she came back to the dorm the next day, one of her roommates saw her and kidded, "you were totally knocked out last night, and I was trying to wake you up because I brought dinner for you and our other roommates). The roommate got the shock of her life when my friend said that she was at home for the weekend and she wasn't at the dorm (Note: this dorm in particular, has a lot of stories about doppelgangers.)
A popular ghost story/urban legend on campus tells the story of a girl who was packing her stuff and leaving for the semestral break. She saw a note posted on the door of her roommates' closet, "Please lock my cabinet when you leave". Thinking nothing of it, she locked the closet door and left the dormitory.
She found out the next semester that her roommate had died inside the closet; she was inside when she left the note for her roommate to find and had starved/suffocated herself in the closet over the break.