For example I was assisting my sister in photographing a wedding. We were taking pictures as the bride was getting ready and I noticed a ketchup bottle on the kitchen table and the following popped in my head
"you should totally spray her wedding dress with that ketchup"
or one time when I was on a fishing boat (in shark infested waters), the thought popped into my head of
"why not just knock that lady there in the ocean?"
I would obviously never do these things nor do I claim to having edgy or mischievous thoughts half the time or even ever but I can't recall any other examples for myself but when speaking of them to other people, very often someone will have similar experiences. A friend of mine confessed to having a thought (which still upsets her if she remembers it)
She was walking behind her Grandmother while very young and holding a pair of scissors and she thought
"Why not stick those in her back?"
I may even be able to google this I just can't articulate it well enough to get the right search results.
Someone in my office said the phrase of this may be something like Hand of the Imp? but I couldnt see anything