If you are writing a web application and need to get microphone data from the user, there really aren’t that many options out there that don’t use flash. I spent some time this month writing an HTML5 wrapper for WebRTC that aims to solve this problem. I call it ‘Simple Audio’ and as far as I know, it’s the only library out there that can solve this problem without the use of flash.
For a demo and source, checkout the project page on GitHub.