I've been playing around with generating sounds in AS3 and Flex. Thanks to this great tutorial over at www.hulstkamp.com I've put together a simple flex interface.
Sound creation is an exciting area in ActionScript that I am just beginning to explore. I thought the code might be useful to other people so I copied the files into pastebin here and here. The following swf requires version 10+ of the flash plugin.
If you're interested in an HTML5 version I have one of those as well.