There you have it, an overview on how to make a great animatronics project (in my case, a turret.). Have fun!
Step 4: Electronics Pt. 4: Movement
You need some kind of movement to catch the viewers attention. Servos are a cheap and easy way to incorporate movement into your projects.
Servos can be purchased online or at your local hobby shop, and they usually cost between 10 and 15 dollars. The Arduino software has support for servos, making servo control as simple as a single line of code.