SoundManager 2 : Using HTML5 and Flash, SoundManager 2 provides reliable cross-platform audio under a single JavaScript API.
pyo : pyo is a Python module written in C to help digital signal processing script creation.
Audio Shop : Your friendly neighborhood script for mangling images or video using audio editing tools.
Soundgrain : Soundgrain is a graphical interface where users can draw and edit trajectories to control granular sound synthesis. Soundgrain is written with Python/...
MediaElement.js : HTML5 and made easy.
One file. Any browser. Same UI.