I picked up some litter and put it in the bin. I actually do this most mornings, when I'm out early, walking the dog. There's usually nobody about, and I quite like it that my good deeds are 'anonymous'.
i do exactly the same...every morning i walk the dog.
AND ive accidentally picked up other dogs poo

...in the dark mornings, i can see roughly where he's pooped, (he's off the lead mostly, no-one around)..wander over with a torch, find a log, pick it up...ooer, its cold. Now ive got to find his

.
Some long term residents who know me know i pick the litter, i do it anonymously, but you do get seen.