Back in the 90s, when my mother was working on a laboratory experiment for her PhD dissertation in a government research institution under the University of the Philippines in a suburban town about an hour and a half away from Manila, she experienced something she never quite forgot. Now this research institution is rather known in the campus as notoriously haunted (although the university, being at the foot of a mountain, also has numerous scary places) because of its isolation (it's about 10 minutes away from the main campus). It is surrounded by quiet fields of corn and other crops, some of which are experimental farms. Also around the building are tall cogon grass.
It was nearing 6:00 PM, and my mother decided to call it a day. Her liquid experiment sample was in a labeled Erlenmeyer flask. In order to find it easily the next day, she placed it in between two distinct trays inside the "Cold room" (so-called because it is where the samples are stored) which is just beside the laboratory she's working in. When she arrived early the next day, she found the flask missing. She was baffled because she really remembered placing it on that spot so that she could get back to it quickly. She checked the spot twice and then looked for it inside the cabinets, big drawers, thinking yet unbelieving that she misplaced it. Exhausted and aware that funny things had happened in that laboratory, my mother said to the room (in which she was alone) "Kung ako ba naman ay tinutulungan mo sa halip na niloloko mo!" ("You could be helping instead of making fun of me!") She turned around to the spot between the two trays it was there! My mother told me she was very shocked, but she gradually became grateful.
This building, which may be described as "in the middle of nowhere", is very quiet after office hours. That is why some staff and students who need to do overtime work in its laboratories are always cautious not to go alone in the CR or in any room if they can help it. My mother told me that in its lobby, a 7-year-old son of a researcher there told his father that he saw various "people" walking around -- marching soldiers, a bloody woman.
Up 'til now, many of my mother's scientist colleagues in this institution have many odd ghost-associated experiences in their own laboratories. I asked my mother how she can work in such a haunted place. She said that once you're busy with your work, you will find it that it is easy to ignore the weird stuff unless they happen directly on your work like what happened to her experiment in the Cold room.