You can yo-yo in space. In 2012, NASA astronaut Don Pettit took a yo-yo on board the International Space Station and demonstrated several tricks. It works because a yo-yo mainly relies on the laws of conservation of angular momentum to perform tricks, which, provided you keep the string taut, apply in microgravity too.
100 Mind-Blowing Microgravity Facts
Prolonged exposure to microgravity (lesser force of gravity in space) can cause muscular dystrophy and bone loss in humans.