There is no better way to learn more about wearables and electronics than creating your own. circuito.io has shared a project that shows you how to use Arduino to make your own Animatronic Tail for your next cosplay event. You are going to need an Arduino Uno, accelerometer/gyro, analog joystick and a few servos to pull this off.
You will also need access to a 3D printer and knowledge of Arduino programming. You can find out more about this project here.