I wish I had thought of this. One time, I was sitting in the car at the local WalMart SuperCenter. I could look out across the street at the Home Depot. It was probably about 1/3 mile away in a straight line. I was bored, and checking out the Home Depot sign on the building. I aligned my thumb and index finger on either side of the Home Depot name, and supposed that the apparent span of the name from that distance was about 1-2 inches. I'm guessing the sign was over 200 feet long for real.
I never did anything interesting with this notion though.