Yesterday was coin-jar payout day for me. I got $120! Woohoo! And since I took my can to the Penny Arcade at TD Bank, formerly Commerce Bank, they counted my change for free, unlike the Coinstars in supermarkets. Perversely, the past few weeks as my coin jar got close to full , I started to really look forward to getting change, to the extent I started to develop some irrational behavior…

Usually my fiancee and I split things pretty evenly but on a few times I knew I covered a little bit more than my fair share because I knew I would get to keep some change. I opted for a smaller cup of coffee because that was 50 cents in change instead of 25. I even felt slightly miffed for a moment when the bagel guy gave me back a whole dollar instead of making 90 cents in change. I knew the more change I got, the quicker my jar would fill, and the sooner I could take it in.

Chase just changed my WaMu debit card over to one of theirs. The flyer says that there’s a “Case Picks Up The Tab” program where “Your next debit card purchase could be on us!” if you use your debit card as credit, you win a chance to have your next debit purchase be free.

In both cases, people are getting nudged into changing transaction decisions into game decisions. You can’t avoid how games operate on your brain, but you can choose which games you play – the ones that reward behavior you want to curb or the ones that promote behavior you want to encourage. Games are powerful, usurping your normal decision-making process. It’s all a question of whether you use that power for good or for evil!

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