Once, while hanging out with friends around a beer pong table, I joked that I trained by throwing pong balls through a tiny tire hanging from a tree. This may be about as close to that concept as you can get.
Lil' Reds sells sets of 1.75 oz cups for beer pong, ratcheting up the skill level required drastically. The daunting odds of winning a game where you're throwing at cups this size is intriguing. I may have just found a Xmas gift for some of my peoples.