September 24, 2012
Following hot on the heels of last week's real-time audio input support announcement in Canary, we have Pedalboard.js, a framework for developing guitar effects boxes using the Web Audio API. Lots of information on the website regarding how it works and how to develop for Pedalboard.js. The whole thing is available on GitHub.
Update: there is now an online demo available! It mostly works on the iPad, although the knobs are not touch-compatible.