auditory binaural beat software

Perhaps this is old news?

http://gnaural.sourceforge.net/

Gnaural is a multi-platform programmable binaural-beat generator, implementing the principle of binaural beats as described in the October 1973 Scientific American article "Auditory Beats in the Brain" (Gerald Oster). There has been considerable research done on the subject since that publication, and WinAural (an early version in the Gnaural lineage) was used as the audio stimulus for at least one published study, "The Induced Rhythmic Oscillations of Neural Activity in the Human Brain", D. Cvetkovic, D. Djuwari, I. Cosic (Australia), from Proceeding (417) Biomedical Engineering - 2004.