I've been reading interesting material on psychological acoustics, physical and granular sound synthesis, real-time DSP for audio, and almost anything else related to generating sounds. My research topic is synthesizing the sound of footfall on snow, sand, and wooden surfaces. If you don't hate Java Applets (or better yet have Java Web Start), you can check it out for yourself and let me know if it sounds anything like sand or snow. I'm sure everybody's going to agree that the boardwalk sounds almost real. The sand is pretty decent too but I still gotta work a bit more on my snow :) Not a big problem because I got plenty of it right outside my bunker.
My biggest problem now is of course trying to render the sounds of water. Liquid sounds are pretty damn difficult to simulate.