WebAudioToy

This is kind of a toy or explorer thingy using various HTML5 techniques which lets you play with Web Audio API. It can play and generate audio, record audio from the microphone (though browser support is still non-existent), create audio using text-to-speech and apply different kinds of effects. You can also do javascript processing to audio in realtime. It supports drag n drop to play your local files and also visualizes the audio output.