Now when you play the 'world's smallest violin,' everyone can hear it -- thanks to Google

There's no better way to express mock sympathy than by playing the "world's smallest violin," but the sad song you mime can now actually be heard. Enterprising minds at creative studio Design I/O have combined machine learning, radar and other technologies so that when you rub your thumb and forefinger together, it actually produces the sound of a violin. Google's Project Soli plays a key role in the magic. Soli is a purpose-built interaction sensor that uses miniature radar to track the motion of the human hand. The sensor and antenna array are packed into an ultra-compact 8mm x 10mm chip.