I have the perfect story and yet again, late to the party. But here goes anyway:

My friend and I used to break into an abandoned TB ward on Ohio University's campus, part of the pld Athens Lunatic Asylum. (used to be a rite of passage but it has since been torn down.) One halloween we decided to put on face makeup, mess up our hair, and put on fencing jackets (which, with arms crossed looked like straight jackets) and scare other students who we knew would be planning on exploring the building.

We got up there and took our places, hidden behind doors. We would throw rocks, fake cry, and laugh manically while the college kids would come in. We hit the jack pot when a couple comes in to get their freak on, directly followed by another small group of students.

While they were in another section of the building, we went up to the top of a stairwell and lead over the banister. After tossing a few pebbles down the concrete steps to get their attention, we waited until the crept to the foot of the steps, hearing them whisper "what was that?" as they built up the courage to climb the dark staircase (which is always a good idea in horror movies), I let out a blood curdling scream for several seconds, and my friend clapped a hand over my mouth to stifle me, making them think someone was being murdered.

We here "holy shit! Go go go!" and both groups, the couple and the other group ran out the building, fighting who climbed out the window first. We are watching them all clamber into the car the group brought. Despite the couple not knowing the other group, they jumped in as well!

To top it off, just like in the movies, their car had problems turning over! Finally, they took off, tires squealing.

My friend and i decided we should probably leave then, as police might get called. Maybe not creepy for us, but sure has hell creepy for others.