Remember Airblock? It is an educational, programmable drone that we covered here a while back. The project has already killed it on Kickstarter. It comes with modules you can connect magnetically and program using a visual interface. Just connect various modules together to create your own drone or hovercraft and control it from your smartphone.
You can use this toy indoors. Airblock is made of a lightweight, engineered plastic foam while its blades are not exposed. You can still support this project on Kickstarter.