Poke Balloon is a toy for Mac that was created without writing any code. Developers and non-developers alike can take it apart and see how it works. It was created with the Vuo visual programming environment (http://vuo.org).
In Poke Balloon, the player can push on the surface of the balloon by moving a single finger across it. Vuo translates the finger position from the Leap Motion Controller into coordinates in a 3D scene. It uses those coordinates to make the balloon "pinched", one of the many 3D object warps available in Vuo.
Poke Balloon was developed rapidly by putting together modular building blocks using Vuo's drag-and-drop interface. Vuo is great for rapid prototyping, even letting you make changes to your prototype while it's running. Vuo can take a prototype all the way to a finished product, with the ability to export a Mac app.
You can download Poke Balloon as a Mac app, along with visual source code to open and play with in Vuo.