I don't know what's скороварка on English, I guess it's an easy rice cooking and heating device that can be set on timer. Buy one, then disassemble it and see where heating elements of that thing are. Tape them on you hard drives, better if they are SSDs, set the timer, put it into a wall socket and leave. If you are of adventurous kind, do the same with microwave's transmitter, pointing it out of the box, but be cautious as fuck because this shit can cook your balls or head in seconds.

or, better yet

You know that most MBs have special contacts for power\reset buttons? You can do two circles to them, one is for you to power up the system normally from some secret button and one from a normal button is to trigger some funsies with things easily triggered by current or heat, like dry gunpowder. So when some ABC agent would try to power up your machine, some funny thing occurs.

and if you are worried about it being disassembled in their lab, print big stickers that stick components to their slots, like OEM fuckers do, and then put cheap razorblades under them near the edge of said stickers. That's a lifehack nazis and then punks used to deny their posters from getting easily ripped off.