Think of something not usually haunted and come up with a reason why it is haunted. For instance…
The Tale of the Haunted Can Opener
It all began with Miss Henrietta Millstone and the can of sardines. Poor Henrietta didn’t know you just needed to turn down the key on the lid. She worked really hard trying to open that can wtih the mighty Pink Power Can Blaster 3001 but it did her no good. In the end, Henrietta was fatally wounded when the sardines (contaminated with radition from the pollution in the lake) got into a little cut on her finger from the rough edge of the can she was butchering open. Henrietta died, still holding the can opener, still stubbornly trying to open that can the wrong way.
Now, on pizza night at the sardine cannery, they say you can still hear Henrietta cursing and shrieking about her stubborn can opener. Her ghost is said to roam the halls, still holding her can opener in one hand and the sardine can in the other. You smell her long before you see her.
Your turn now. Don’t forget to come up with a good name for your ghost.