So evidently there is such a thing among the youth of America - at least in this part of America - known as "cup-stacking." It seems as though it's positioned as a sport and to hear my kids talk about it, you'll probably want to start looking for it in Future Olympic Games.
Griffin has asked me a few times over the past god knows how many months for cup-stacking cups, a request that due to my own ignorance and dismissiveness of the entire concept, I let slide by, unheard. So thankfully, Griffin's friend Grant gave him a complete set of cups, complete with cup-stacking mat and timer.
Griffin was pretty excited about this (Rowan too, actually, when Griffin will let her use his gear) and has spent some amount of time trying to improve his time on this particular sequence. Right now, I think it's 21 seconds.