This speed project from Design I/O ( design-io.com ) uses Google's Project Soli - Alpha Dev Kit combined with the excellent machine learning tool Wekinator and openFrameworks to detect small movements that look like someone playing a tiny violin and translate that to the volume and playback of a violin solo.
XKCD - World's tiniest violin reference:
xkcd.com/743/
Project Soli:
google.com/atap/project-soli/
Wekinator:
wekinator.org
openFrameworks:
openframeworks.cc
