Michael Persinger built a device that stimulates the brain with electromagnetic waves. He claims the machine, generally known as the “god helmet,” can induce religious experiences. His experiments have never been successfully replicated, but a group is trying to build an open source DIY god helmet:
The project is in a very early alpha stage. Some of the current goals for the project include:
-Create a workable and easy to build hardware design to allow experimentation similar to that done by Dr. Persinger.
-Develop firmware for any integrated controllers
-Develop software that facilitates controlled application of TMS or rTMS utilizing the hardware
-Software integration with openEEG and Sbagen for a rich experimental environment
Update: There still hasn’t been a release, but it looks it’s still under active development as of March 2013.