The Ghostly Ringer

I was sitting in the living room last night, and then, there were Six to Eight loud rings of the Front Door Bell. I could not be bothered to answer it, and my father did. He went to the door to deal with whoever was ringing the bell, and switched on the outside porch light, and looked through a Spy Hole and found that there was no one there. He immediately checked around and found no one. In itself, it is not really paranormal activity, and could be kids larking about. The Doorbell is electronic so, it does pick up other Doorbells that operate on similar radio frequencies so it possible that is what happened.
There are some Spirits and Ghosts, such as Poltergeist who can use the electrical systems as well as Lights of buildings, to frighten the living, some also can effect computers with no sign of the intervention of the spirit. I have personally encountered the rapid switching on and off of lights, a classic trick of poltergeists, which they use to communicate. It is not just restricted to them, but to other Ghosts and Spirits as well. In the Office Poltergeist encounter, the lights would go on and off, in rapid succession, or sometimes would be switched off. When I was working late in the Office, I witnessed it personally on many occasions. All the Lights seem to switch off in one go, and the one above me stayed on. I checked them all out, and found they worked, and were not broken.
On its own the ringing of the Doorbell could be taken to be children larking around in the street outside. Later, I prepared for bed, and when I went to my room, I checked my bed which was all neatly and cleanly made, and folded correctly, and there was no sheets out of place and a tucked in Blanket covered the whole bed.
Later, I brushed my teeth and left for about two Minutes, and when I returned, I found that the whole of the top right corner had been folded back exposing the sheet underneath.Neither my father and I, had been into the room, so I am can assume that it was a spirit of some sort, letting me know that it was around.