The first time Aaron slugged my shoulder to express his joy at seeing a shiny new Toyota Prius glide by, I didn't know what to think. Was this the grown-up version of the punch buggy game my brother and I tortured each other with every time we saw a Volkswagen beetle? If so, how had the stakes changed 20 years and 100 pounds later? And, more importantly, what were the rules??!!

To figure out the game, I began a first phase of consumer research: namely, me punching random people on the streets of New York to see how they reacted when I screamed "That's a hybrid!" in their faces. Some people laughed. Others, the early adopters as we call them, nodded in approval, quickly processing what had just happened, understanding the sheer genius of the game, marveling at the viral potential, and immediately scanning the streets for another Prius to get even. Others, let's just say, haven't caught on just yet. There were, I admit, a few insults. A few threats. Many just took off running, perhaps confusing the game for tag. Yes, there was a big guy with a big fist and tiny dog who got in my face saying, "My hummer will crush you, earth lover." I ended the consumer research phase when an increase in the national security alert level made folks a bit too jumpy and suspicious to play.