Ref is a wearable pet made by Jens Dyvik. Its goal is to assist you in improving your emotional skills by mirroring your state of excitement through its behaviour. By sensing your heartbeat, Ref will respond through non-verbal communication. For example, if Ref detects that you are stressed, it will raise its head and tail, otherwise, when you get relaxed  Ref will curl up its tail and lower its head. The system is controlled by six servomotors and an Arduino.

via [Fashioningtech]