If you haven't seen it yet, over at Sparkfun on the Enginursday blog that is published on Thursdays, they used a Teensy 2.0 to make a Sip-and-Puff work-alike, which is a device that can act like a mouse for people who can't use their hands, by alternatively blowing and sucking air through a tube at specific intervals: https://www.sparkfun.com/news/1570