"Beercade uses a custom-made system that re-utilizes certain retro nostalgic arcade machine user actions for its concept, " explains McKinney Creative Technologist Adam Carroll.

ENGADGET: Beercade replaces arcade coin slots with beer taps, rewards winners with brew

Snapshots of the user's acoustic patterns were sent to a remote server, where the user's emotional state would be calculated by a machine-learning system.

CNN: STORY HIGHLIGHTS