Way back, there was a lightning (1 hour?) game programming contest over at FlipCode[1] IIRC where someone had made a Flash-based Tamagotchi spoof called Tamagraniti or similar, where you had to take care of a rock.

The interface was exactly like the real deal, and like the real deal you could water it, try to feed it and even give it a pet pebble for company. All with the expected results.

I loved it and I regret not saving a copy of it.

[1]: https://flipcode.com/