I don't know if Little Free Libraries are whimsical enough, but they were discussed recently: https://news.ycombinator.com/item?id=47211280

I remember when I was very very young in my small city (~100,000 people). In the summer time after say 6:00PM, people would sit on their front stairs and also take short walks around the area, socializing with everyone they met for a few hours.

That came to an end in the late 60s, early 70s. That was going on in all the neighborhoods throughout the City. Maybe people will start doing that again in the areas that have this "whimsy".