An open source project enabling microcontroller synthesized binaural beats synchronized with LED lights continues to hold my attention. The Make Magazine solder and software instructions along with kit parts helped me to build several versions of the device. I'd never stuck with listening to recorded binaural beats before but the brush fires this particular project triggered finally moved me to spend the $20 to order the basic kit that needed to be modified using the helpful instructions freely available.
The web community enthusiasm and thrill of the build fueled the sprint to my first use; the hot glue had hardly cooled. The visual effects got my attention. Previously unimaged colors and patterns came from my own brain. Clearly I'm visually oriented and I didn't focus my attention exclusively on the audio generated until about two weeks of daily use of the device. It generated the same "brain-wave states" but without the visual effects that set the hook and seem more powerfully entraining.
You can browse through the reference links and continue reading about this sound and light machine, which is sometimes called a mind machine, and visit some of the sites I found most helpful. I've included a recording of the sound portion of the standard program that comes with the initial firmware installation.