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Did you make a robotic coffee pot which implements HTCPCP and decafs unauthorized users? Show it off here!
By wholder
I’ve designed a small circuit you can build which lets you power an Arduino On, or Off by pushing a button, or responding to an external signal, such as from a sensor. You can also use this circuit with a Real Time Clock (RTC) module to power on an Arduino at a particular time, or date and time and then lets the Arduino power itself off when done. The circuit consumes only microAmps when off, so you can use it to build systems that can run for months using ordinary batteries.

You can find out more by watching the following videos on my YouTube Channel:
Or use the following two links to read the more in-depth articles that accompany these videos on my Blog, Wayne's Tinkering Page:
I've written an Arduino library to make implementing pushbutton power control easy and a separate Arduino library for the DS3231 RTC module to simplify time-based control as well. I hope you find these useful. If so, please comment here, or on the YouTube videos.