I want to add a couple of good ones I’ve found:
Jeff the Killer lost media: no one knows where the original Jeff The Killer image came from.
Mortis.com: old weird website
Also here’s a good website on various obscure computer/Internet related oddities: https://suricrasia.online/iceberg/
Does this count? An oldie but a goodie.
https://timetravelinstitute.com/enigmas/john-titor.1/
I love the John Titor story, because it’s so detailed and rich, but it obviously has to be fake because the 2038 issue has been solved by 64 bit timestamps, and it’s impossible that we wouldn’t have advanced to 64 bit processors because of the RAM limits that 32 bits impose. Phones have more RAM than what a 32 bit computer can handle, and we’re over a decade away from 2038.
It’s like someone claiming to be a time traveller going back to the 50s to get an abacus to help prevent the Y2K bug.
Steins;Gate season 1 did it better. =p
Steins;Gate VN did it better than the anime.