The HTML5 specification introduces the audio and video media elements, and with them the opportunity to dramatically change the way we integrate media on the web. The current API provides ways to play and get limited information about audio and video, but gives no way to programatically access or create such media. We present a new API for these media elements, as well as a working Firefox prototype, which allows web developers to read and write raw audio data. Through numerous working demonstrations, we show how access to this data allows for improved web accessibility, opens new possibilities for real-time media manipulation, and extends the web in ways that have traditionally required proprietary plugins. For example, we look at how an audio data API can be used to create such things as in-browser synthesizers, audio based animated visualizations, digital signal processing, text to speech, etc. We will also explore the code necessary for web developers to work with audio data, calculate FFT, and other audio algorithms in JavaScript.