Steven from Rimstar.org built an interesting spooky Halloween skull to scare anyone who walks by. The video below goes through the construction details.
“Two heads on a body are scarier than one so for halloween I mounted an Arduino controlled skull on my shoulder with the electronics in a backpack and a hand controller hidden in my hand with the cable running down my sleeve. The jaw opens, the eyes light up and it makes a scary sound.
The biggest issue I ran into was getting a sound synthesis that could be done by the Arduino while still using a servo. Most sound libraries I found either conflicted with the servo library or required use of an abstraction layer.
Luckily the Arduino comes with a tone() function that uses simple PWM to make an 8-bit type sound that did the job while not conflicting the the servo library.”