Can a microcontroller control its own power?  Well nearly! An ATX power supply, either new or from an old PC, is a great way to power Arduino and other microcontroller projects.  That is covered in several 'ibles such as this one.  However, because of some of the special features of an ATX, we can use it as a "smart" supply that's even better. This is a very simple 'ilbe that will allow you to make a lead t ...