Honesty with incentives
There are a few interesting incentive-related tidbits in this Slate article titled Stop, Thief! Thank You. on the absence of looting in Japan post tsunami:
For example, if you find an umbrella and turn it in to the cops, you get a finder's fee of 5 to 20 percent of its value if the owner picks it up. If they don't pick it up within six months, the finder gets to keep the umbrella. Japanese learn about this system from a young age, and a child's first trip to the nearest police station after finding a small coin, say, is a rite of passage that both children and police officers take seriously. At the same time, police enforce small crimes like petty theft, which contributes to an overall sense of security and order, along the lines of the "broken windows" policy implemented in New York City in the 1990s. Failure to return a found wallet can result in hours of interrogation at best, and up to 10 years in prison at worst.
It's also remarkable to see organized crime 'pitching in' with humanitarian support and enforcement. While this is self-described as compassionate behavior, peace, stability and order are actually the necessary conditions for Yakuza-style organized crime, so there doesn't seem to be any incentive to do anything but try to promote a return to normality.