Well my first night alone at the gas station I work at I discovered there's a ghost in the wall that only kicks when no one else is around.

Also when I'm home alone, I put things in front of the windows like squeaky dog toys and the fan and what not, hopefully to make some curious entrant trip up. I haven't had a chance to test it yet, though, so...I don't know if it works but it makes me feel better lol