We put up a swinging chair on a heavy duty hook in the basement too, and although its quite limited in how much swing there is, the sheer delight in climbing on something suspended in the air seems to work out a lot of bounce.
Our indoor swing is from Ikea, and it’s made of a canvassy kind of stuff, with an air filled cushion. You can fit about nine children in it if you aren’t concerned with how well they can breath. Sometimes we hang our hammock from the same hook. Just for a change of pace. Breathing isn’t really any easier.
For the toddler types, we have always made sure that we have one of those Little Tikes plastic cube climbing and sliding things that we drag in for the winter. I usually put it somewhere very inconvenient like in the kitchen. They make two sizes, one for wee toddlers, that sits about a foot and a half high so they can’t fall very far, and another one that is about 3 and a half feet high for bigger kids.
Worth their weight in solid sanity.