Arduino to Arduino Wireless Communication

Here is a video explaining how to setup two Arduinos to communicate wirelessly with each other. And here's a link to the instructions: http://www.instructables.com/id/Long-Range-18km-Arduino-to-Arduino-Wireless-Commun/. This could be useful if we want to have one Arduino inside of a puppet sending data to another Arduino outside of the puppet. I've never really worked with Arduinos before, so a lot of this stuff is totally new to me. Hopefully this is somewhat useful though.