And you know, whatever you find laying in your grandparent's basement. That usually does the trick.
Instructables user cbaabc73 came up with a cheap and easy way to turn off outlets when you aren't using them. He built it after noticing his wife kept leaving the curling iron plugged, which can be extremely dangerous. This DIY project takes only basic tools without the use of soldering.
UK not-for-profit Eggs for Soldiers built a life-size tank out of 5,000 cartons to help raise awareness for its upcoming March Fourth Help for Heroes Campaign.
Instructables user PDRWLSN created this pocket-sized flame thrower not because it's freaking awesome, but to as a way to start a quick fire when you're camping and only have access to wet wood. The gun uses materials readily available at any hardware store with butane lighter fluid as a fuel source and a BBQ ignition switch as a trigger. Below is a video showing the machine failing to melt snow. If any of you are crazy enough to try this, please, be safe.
Steve Hoefer at Grathio labs shows off his Arduino based door opener, which responds to knocks on the door bye timing the gaps between the sounds. If the gap matches the programmed knock, it unlocks. Let's never use keys again!
Know a little bit about Arduino and care to make your own? Check out his Instructables post!