Many years ago when my mother moved into a house that backed up to our property, I installed an X-10 remote control system in her house so that if we had to go over there in an emergency we could turn on her lights from our house to get to and into her house. Of course we already had an extensive X-10 system in our house.
On one of their visits to us our daughter and her husband stayed at my mothers house. He, being one of the only four people I've known who used X-10 early on, immediately noticed the X-10 remote control on the living room table.
About 10:30 that night as we were getting ready to go upstairs to bed all the lights in the house started to behave erratically and we were madly running around trying to figure out what was happening.
Our daughter, her husband and my mother were out in our driveway in hysterics (particularly my mother) watching us frantically run around. My son-in-law had plugged my mother's X-10 remote control into one of the outlets we had on the driveway fence to plug in the block heaters for our diesel powered cars, and used it to randomly turn our lights off and on.
Be careful, it could happen to you.