This video, via Peak Eleven, takes a look at using the TEControl BBC2 breath controller.
The BBC2 is designed to let you add expression to performances. It adds four additional options for expressive control: breath, bite, nod & tilt.
Live Demo + Overview of the amazing MIDI Breath Controller from TEControl (BBC2) for adding expression, motion and emotion to your software instruments and performances.
This is a USB Breath Controller that converts your input into MIDI CC values which you then map to your software instruments and sample libraries to control expression, dynamics, filters and basically anything that you can map MIDI CC to.