One of the teachers I used to work with has a ranch where he keeps a menagerie of creatures, including llamas. This robotic display was inspired by a tweet he made about being spat on by one of them. 
The llama's neck moves with a simple cable mechanism on both sides which gets pulled by a servo. The lights go off to trace the path of the "spit" and there is a second servo for the bucket to "sell" the illusion. Powered by a HummingbirdBit.