Earlier today I watched a series of people randomly stab the crossing button, despite it already being lit and them being oblivious to the fact that this is just a game local councils play (I'm convinced the button isn't actually connected to anything except the "wait" light), at a Pelican Crossing.
Seeing this, I wondered idly if there was a way to deploy finger print technology here. Not for identifying people, but for differentiating them from each other. The crossing could easily know what the flow rate of cars was and then compare it to the flow rate of people (ie the number of people who've pressed the button since the last time the lights were red). A single person would wait longest, lots of people would wait less time. Knowing that there was some impact of pressing the button might reduce the people who dart across the road, dodging traffic and so reduce the risk of accidents.
I can see all kinds of opportunity for social interaction here: "hey buddy, could you press the button too, I need to cross the road quickly". Just wondering.