I originally prototyped an interactive headset as an accompaniment to ur cardboard pet for MCDA's "inter:connected" exhibition in June 2016.
I later revised the project for HeK's "The Unframed World" exhibition in January 2017 with a series of 5 Google Cardboard attachments.
The attachments respond to the user's grip by "blushing" with LEDs, pulsing with a heartbeat, and warming up. The pressure of a grip is treated as a variable that determines the number and color of LEDs, the speed of the heartbeat, and the amount of heat generated by a peltier element.
The device runs on a single LiPo battery and makes use of a Sparkfun microcontroller. The source code is available here.