I love it when you can cut through pages of format specification to deliver something simple. To that end I added another minimalistic code gem - WAV file writing in a single function. It only supports PCM format, but its amazingly handy when you need it! :) If you want to see DPCM format support post in the comments or send me an email.
Among other things, I've also been hard at work in my off time on a single file, minimalistic MPEG file writer.