A group of us are trying to get this idea going. Take 98% of your time for yourself, family, friends, work, vacation… But give 2% to Total strangers.
For instance I get people telling me their big plans fro t-shirts or greeting cards. 90% of them are just Bs’ing. But if you recognize someone willing to put in the work, give them some old art supplies, help them with a website, teach them how to distribute work…
Just smile or let a car into traffic. Any random act of kindness really.
I mentioned this in another post a little while back I believe, but when I was at college, half a lifetime ago, they said to us, once you are in a position to, always try and give 10% of your professional time free to community and charitable projects.
As to letting people in at junctions, opening doors, smiling, etc it is almost sad that we even need to point this sort of stuff out. Random acts of kindness should be second nature – just part of being human. It is a sad indictment of modern society that generally we don’t any more.
Does volunteering here as a moderator and responding to endless newbie questions count? 
Oh yes. Most definitely.
Well yes, but I am thinking more in the complete stranger mode because I feel people in general are losing faith in other people. Everyone tells us that “they” are lying or wrong or whatever. We are a divided society where no one knows what’s really going on.
Therefore, I believe the only way to get around that is to be completely anonymous. If people start encountering good “vibes” on a regular basis maybe they’ll be less likely to color all of any group a certain way.