From Noromaa Solutions:
BrainWave Generator is a brain-stimulation application that creates sounds with binaural beats. It can be used for relaxation, meditation, enhancing learning capabilities, sleep induction, self-hypnosis, and more. You can add a wide variety of new effects, including background voices or noise, up to four independent sound channels, and sound waveforms. Version 3.1 includes a visual stimulation feature that flashes the computer screen at a set frequency. It also includes several more sound parameters than previous versions.