I have a small windows application that I call the Audio Bilateral Stimulator, that sends alternate pulses to each ear at a predetermined frequency. I originally wrote it for use with EMDR (Eye Movement Desensitization and Reprocessing) work, but it has proved useful in a number of other ways and I'm thinking of expanding it's functionality. It's available to subscribers to my newsletter from
Hypnosis Audio CDs.
I also created an audio file with a simple loop and and a brainwave entrainment to match the brainwave cycles of experienced meditators... it's not a pretty sound, but an interesting experiment which I could give you a link to an mp3 version if you were interested.
Love and light
Adam