I just got back from doing something I haven't done in over twenty years: playing wallball.
Now, Googling for "wallball" reveals several different games by that name. (Including, oddly, some stupid computer screen-saver program to train PHBs in their jargon. WTF?) But the proper way, of course, is the way my brother Jim and I used to play in the alley.
The house where I grew up was located at the confluence of two alleys T-ing together, our house at the top of the T, making a nice wide playing area out of the junction where they opened into each other. The house across the alleys to the right (looking up the T toward our house) was home to a snowball business that operated out of a truck; it was, to us, the "snowball truck yard", I don't think I ever knew the names of the people who lived there. The truck was kept on a parking pad at end of the yard, which was separated from the higher ground of the rest of the property by an cinder block retaining wall about six feet high. In the summer, the truck was out selling ice with flavored syrup most of the time, leaving us the perfect playing field.