Doorway Jungle Gym
First the bad news: install this jungle gym contraption in your doorway and the odds you will get inadvertently divebombed or kicked in the face by the child using it as you walk by one day are close to 1:1. And now the good news: the support bar that wedges inside your door frame has a 210-pound weight capacity, so if you remove its attachments you yourself can use it for chin-ups and leg raises and "accidentally" return the favor down the line, say when little Timmy is heading to the john in full Nintendo-3DS-absorption mode.
The depicted doorway jungle gym kit includes a support bar, strap swing, and trapeze bar. Additional attachments, such as a net swing, gym rings, a rope ladder, and a cuddle swing, are purchasable separately. This is a really excellent, efficient, and relatively inexpensive way to determine if your kid is cut out to pursue his or her dream to become an Olympic gymnast, has the coordination to make it worth your getting up early on Saturdays to attend pee-wee sporting events, or should be removed from athletic pursuits altogether and stuck in piano lessons.