Killing a Tamagotchi
The girls used to play with them in school and would often conveniently leave them behind at their desks for mischievous dorks like myself with nothing else better to do to mess with. Although I don't think I personally was brave enough, or mean enough, to do the dirty and (moderately) hilarious deed, I do remember at least consenting to it, and perhaps aiding and abetting the real perps. Either way I plead the fifth... and insanity.
Now the easiest way to kill a Tamagotchi was to press that button on the back (which would "reset it") and leave it behind for the owner to figure it out a half hour later when the thing wasn't crying for even just thirty sustained seconds. I think we were doing the school a favor, actually, taking these things out. The other way was usually more time exhaustive, but a lot more fun, and involved feeding it like a nervous eater on a roller coaster. Feed it until it's wallowing in its own waste (and believe me, these guys really are little machines!). It won't take long after that.
The pure enjoyment of "Hey! You killed my Tamagotchi!" was so brief, but then the chase was on. Hell hath no fury like a Tamagotchi owner scorned, and I don't think I have to tell you who's life they considered more valuable. This is ironic, seeing as the typical Tamagotchi died at least a couple times a day anyways... heck, you could accidentally kill it. Just sit on it for a long time. It's got to suffocate eventually...
These days, there's probably an app for it.