Airhorner with added Web USB
I received a very cool gift this year: a Web USB-powered airhorn! It uses an Arduino Uno and some very neat code. The device waits for approval, configures, and reads continuously from the device for an "ON" signal to trigger the horn. Although the Arduino code isn't available yet, the project is inspired by the WebUSB examples for Arduino and should be released soon. Check out the post and the demo.