One of the thing about my son is that whenever there is something in his mind, it sticks with him. When he learns about something, if it interests him, he will talk about it, constantly. I remember a few years ago when his former school was teaching the kids about safety.
In particularly, they were teaching the kids all about the different types of street signs. My son took a great deal of interest in identifying all the different signs. One of his favorite road signs was "Pedestrian Crossing." He also like "Railroad Crossing" and "Speed Limit" signs.
Another thing that my son likes to do is count things. It all started when he would count the points he would earn in school each day. Now he counts everything. There are a couple streets in our neighborhood that has multiple "Pedestrian Crossing" signs. To this day, every time we drive down that road, we count the "Pedestrian Crossing" signs together.
When I am out driving around doing my pizza deliveries on the weekend, I have seen a few custom road signs while making the rounds. I especially see them in neighborhoods with a lot of families with kids. Signs exhorting drivers to go slow because children are playing.
Personally, I have thought about getting a couple signs for my own house. I hate having people come to my door to try to sell me something. We get a lot of sales people offering us free estimates on new windows. I am thinking a good "No Trespassing" or "No Soliciting" sign might be appropriate for me. Or maybe this home protected by Smith & Wesson.