Couple of thoughts... firstly, I love the concept of this thread. As I look forward to my own retirement this summer, even though my next chapter will be a busy one, my sense is that I'll have more time to devote to things like community building, volunteering, and random acts of kindness.
Whenever I'm moving to a new place, I always like to get a sense of the community. One way to do that is by joining the various community Facebook groups for where you'll be living. You can get a real sense of the good, the bad and the ugly by sifting through these groups. One thing I've noticed about the place I'll be moving to post-retirement, is that people in need will make posts asking for assistance. It might be someone who needs a ride into town, or someone who needs $50 to pay their electric bill.
I'm increasingly convinced that these kinds of micro-philanthropic interactions can be a super effective way of making a difference in people's lives, and in our communities. Just imagine the pure joy of providing an opportunity to someone whose life would be completely transformed by a mere $1000. I'm going to focus on that kind of giving back, once my uniform is neatly folded, in a mothball-filled box in the attic.