I was also good at playing "Butt's Up" and its variant "Suicide."
These games required a rather large wall, a tennis ball, and a bunch of kids. A kid threw the ball at the wall. Anybody could catch it--one-handed catch only--and then throw it at the wall without it bouncing on the way. If the kid caught it with two-hands, dropped it, or the ball touched the ground (bounced) before hitting the wall, that kid (kid1) had to run and touch the wall and any other kid (kid2) could get the ball (one-handed).
In "Butt's Up," kid2 would throw the ball at the wall. If it got there before kid1, kid1 had to kneel down, tuck his head down, and put his butt up. Kid2 then got to stand at a set distance and try to hit kid1's butt by throwing the ball at it. A variation had every kid playing get the chance, but that could take too long.
In "Suicide," kid2 would try to hit kid1 with the ball while kid1 was running to touch the wall. I was very good at popping people in the back of the head as they ran, for some reason. That actually hurt less than getting hit in the back.
Does this game sound familiar to anyone, under any other name?