Two asides: First, it’s interesting to note that no one (zero) gets paid to put up Christmas lights, but some towns are awash in them.
and second, I think there’s a parallel to the broken windows theory here. Broken Windows asserts that in cities with small acts of vandalism and unrepaired facades, crime goes up. The Christmas Light corollary might be that in towns (or online communities) where there’s a higher rate of profit-free community contribution, happiness and productivity go up as well.
Source: Seth’s Blog