If you want to get your hands dirty on a semi-evil electronics project, this DIY EMP generator is fun - if not a little dangerous - build to try. It won't fry much, except at extreme short range, so you should be careful with it, but you'll learn a lot in the process.
It's Evil Week at Lifehacker, which means we're looking into less-than-seemly methods for getting shit done. We like to think we're shedding light on these tactics as a way to help you do the opposite, but if you are, in fact, evil, you might find this week unironically helpful. That's up to you.
The video above tells the tale, and the project is actually the work of YouTuber FPS Weapons. You can see near the end of the video how he used it to make an old Game Boy Advance boot loop itself, and how he fried a couple of old smartphones. Of course, if you build it yourself, you shouldn't run around killing people's peripherals, and anything even remotely well shielded can stand up to what this will put out - but the process of building this will teach you a bit about electromagnetic fields, and how to generate them and how strong they can be based on the power source you provide. Hackaday notes:
The device is pretty simple. A DC source, in this case an 18650 lithium battery cell, sends power to an "Ultra High Voltage 1000kV Ignition Coil" (as the eBay listing calls it), when a button is pressed. A spark gap is used to dump a large amount of magic pixies into the coil all at once, which generates a strong enough magnetic pulse to induce an unexpected voltage inside of a piece of digital electronics. This usually manages to fire a reset pin or something equivalent, disrupting the device's normal operation.
While you're not likely to actually damage anything in a dramatic way with this little EMP, it can still interrupt an important memory write or radio signal and damage it that way. It's a great way to get the absolute shock of your life if you're not careful. Either from the HVDC converter or the FCC fines.
That last part is important to note, so if you do decide to try this project, keep it to the confines of your own home, or the local hackerspace, where you can be free to experiment with things like this.