OK, here's another.
Years ago me and my mum, dad and brother moved into a flat. It was in a gorgeous old terraced house near the centre of the city I grew up in and took up the whole top floor. The ground floor was a separate flat.
When we moved in we found those home made Palm Sunday type crosses everywhere - in drawers, cupboards, pinned to walls, there was even one in the shower. We moved in in August, so a long time since Palm Sunday! We threw them all away.
The first night we were there, I was woken several times in the night by a REALLY loud rumbling sound - it was like a heavy train going down tracks, that's the only thing I can liken it to. I was more annoyed than anything else. Next morning when I mentioned it to my family, nobody else had heard it.
Over the next few weeks, other strange things happened. My cassette player (it was the 80s 
) would turn itself on and off - and by that I mean I would see the play button depress by itself, not just a radio randomly turning on. One I was lying in bed and watched as the (tightly screwed on) lid of a bottle of still mineral water I'd left on my desk shot off and hit the ceiling above like a champagne cork, and the water fountained out of the bottle.
Meanwhile, a girl had moved into the flat downstairs. We spoke to her a few times, she was a doctor and really lovely. She asked us if we had the same problems with the plumbing - apparently it clanked and screeched all night and she couldn't sleep. We hadn't heard a thing. A week after she moved in, she left. She was there in the evening - we saw her come in from work at about 10 - but was gone in the morning. For some reason though the lock on her door was broken and the door to her flat was left open (the individual doors were inside the building isywim).
It was a really hot summer that year and our flat was often sweltering. My mum had decided to have a nose into the downstairs flat and discovered that it was much, much cooler than ours. In fact in the evenings it was so cool you could see your breath despite it being in the high 20s outside. She took to sitting down there to cool down, and I sometimes joined her. We would often open the lounge door to see a sort of strange cloud hanging in the middle of the room at about eye level - it was greyish white and less dense than a normal cloud. It would sort of fade and evaporate pretty quickly after we came in. It struck us as a bit odd but we figured it had something to do with how cold it was compared to the warm air outside.
One night my mum went downstairs alone to read - it was uncomfortably hot upstairs and she couldn't sleep. She opened the lounge door and saw the cloud (the room was dark). With her next step, her bare foot was sliced by a shard of glass that that had - by the way it had entered her foot - obviously been 'standing' on its edge. Hard to explain but it was a triangle of glass about 10cm along its base and maybe 5cm tall that had somehow been standing on its bottom edge and the narrow top point had gone into her foot. The 'cloud' remained all through this and when we got downstairs to her (the glass still poking out of her foot) it was still there. It stayed when we turned the light on, and only then began to slowly 'evaporate'. We saw that there was a framed picture of a boat on the wall which had a triangular chunk of glass missing from the frame - no other cracks, and it was still hung securely and straight. We took my mum to casualty but none of us ever went downstairs again. A young couple moved in shortly after but moved out within a fortnight.
The weird stuff upstairs continued and we were getting seriously freaked out, so my mum started looking for somewhere to move to. We found a new house and were all set to go by the middle of October. On our last night, my dad and brother were out and me and my mum were watching a film. Suddenly we heard somebody running up the stairs to our flat which we immediately though odd as we hasn't heard the big main door downstairs slam as it always did when somebody came in. We waited for the sound of keys in the lock, thinking maybe it was my dad or brother, but no sound came. We just started to relax when the most almighty banging started on our flat door. Somebody was hammering on the door so hard the stuff on the mantelpiece was shaking. We were terrified - we went out into the hall and the door was shifting in its frame the banging was so hard. It was as if somebody was trying to smash the door down. This went on for several minutes. My mum and I were screaming and crying, sure that whoever it was would soon succeed and smash the door down. Then, suddenly, it stopped. After a few seconds I went to the peephole but of course, nobody was there. Eventually we plucked up the courage to open the door to find the stairwell empty. We went downstairs, past the empty flat which was now securely locked, to find that the big heavy front door was locked from the inside with the safety chain on. We had not locked it or put the chain on, as we were expecting my dad and brother home. There was nowhere for anyone to hide in the downstairs lobby, it was just a square a couple of meters across.
We were so, so glad to move out the next day.