good idea, but i doubt your average Jane Doe with two kids in the back of her Chelsea tractor will know what it means.
The kids will be shouting flashy lights and the woman may think its related to disco beats or something.
Bottom line they may find they are going to have to re educate the whole public on this. not to mention the agro you are going to get from the local plod to start with while this thing breaks into the mainstream.
Near me, they hate any kind of lighting on bikes and cars that is not standard and legal. So this i can see may come across as some chav flashing fast and furious style thing...until you tell them and then they will just say
"yes i see it, you are the best"
I think