Played catcher on my command softball team back in my Navy days. Obviously not as involved or hazardous as doing it in baseball, but it was fun. Didn't do it long enough to hurt my knees. I liked being involved in every play - I remember one inning where I made all three outs - caught two pop-ups and tagged out a runner at home. Nothing better than tagging somebody out when they're trying to score on you. I always tried nail them in the head, too. Accidently, of course.
I wish now that I'd stuck with it. Oh well.