I wave at just about everybody. About 4 miles of my commute was on muti-use paths and there was a guy I regularly saw with no arms, he had prosthetics. He would wave back at me every single time! It gave me warm fuzzies that I could always count on him to acknowledge my existence. I moved a few months ago after not commuting since the start of COVID, I'll miss having that interaction once I have to commute again.