Free Online Guitar Tuner built with HTML 5 Web Audio API
I've been playing around with the new Web Audio API features and have completed my first web app.
As far as I can tell, it's the first of its kind, an in-browser Guitar Tuner that uses the microphone and no flash whatsoever.
Hope you find it useful and/or cool: freetuner.co
Note that only firefox and chrome are supported.