Ride your own brain waves! You don't have to be a Buddhist monk to meditate, or a Sleeping Beauty to sleep well. Achieve these altered states of consciousness, and others, with this simple microcontroller device.

What would happen if you could play a recording of brain waves into someone's brain? It turns out that there are devices that can do this. Sound and Light Machines (SLMs) produce sound and light pulses at brain wave frequencies, which help people sleep, wake up, meditate, or experience whatever state of consciousness the machine is programmed for.

This article shows you how to build an SLM for much cheaper than you can buy one. We'll do it the easy way, by hacking a microcontroller project that already exists: Limor Fried's Mini-POV kit. This cool toy blinks pictures and words in the space you wave it through, and we can transform it into an SLM simply by changing the firmware and some minor hardware.

This project originally appeared on the pages of Make: Technology on Your Time Volume 10.