Lung Flute by Medical Acoustics

I read about the Lung Flute in Popular Science. It's a device that you blow into, a bit like a flute but more like a recorder, that helps you expel mucus and phlegm from your lungs.

How it works
The body naturally gets rid of phlegm by using hairs that "wave" it towards the top of the throat. These hairs wave at about 17 Hz. The Lung Flute creates pressure fluctuations at the same frequency, assisting these hairs.

Buying
The Lung Flute is ridiculously hard to buy. It's only available by prescription in the U.S., but they ship to Europe as well. I bought it from vPost Asia, a service by Singapore Post that lets you buy things from the U.S., Europe or Japan. It works by giving you an address in the 3 countries that you ship things to, then vPost ships your purchase to Singapore, India, Thailand, Malaysia or Australia. This lets you buy things from shops that only ship to those 3 countries.

Replacement reeds for the Lung Flute

The most important questions that the videos online don't address are "what does it feel like?" and "does it work?"
When you blow into the Lung Flute, at first there is resistance. Then, the reed flaps to the other side and the air can flow freely. The reed flutters rapidly between the 2 positions, so the air alternates between restricted and free flow. The net effect is it feels like coughing quickly and shallowly.
Before you think it's going to let you cough up mucus from deep in your lungs you didn't know you had, temper your expectations with these: the human body is naturally very good at expelling mucus. A healthy person will not produce excess mucus that needs to be removed. What these mean is that unless you have an abnormal amount of mucus or difficulty coughing it up, the Lung Flute will not be of much use to you.

More reading:
http://medicalacoustics.com/
PopSci video