You are right, they are very interesting in their displays of intelligence. One time when I was hunting, there were a group of crows near my camp site. They would come down and investigate where I was staying looking for any scraps of food. As soon as my gun was visible they would all fly several hundred yards away and observe me from a safe distance. Once I put my gun away they would all return back to my camp site to look around.

It was very clear they knew exactly what the gun was, and knew to stay clear of it when they saw it. I never thought about crows the same after that.