The 404 page started out as the catch-all page you see when a site can't find the page you are trying to visit. That page is an afterthought on many sites. but a few websites have devoted time and resources to making their 404 a destination worth visiting.
This blog has a simple 404 page which references creatures living in the server closet, but other sites have put more work into it, with some crafting games just for the 404 page, or funny images, or even a video (which has since been deleted, alas).
Amazon went for the more personal touch. A Twitter user has tipped me to the news that starting sometime before May 2016, Amazon replaced its uninformative and unhelpful 404 page with one which looks like this:
The 404 page now features one of the dogs belonging to Amazon employees, and it also links to a page called "Meet the dogs of Amazon".
That page features the dating profile of a couple dozen dogs, including a disappointingly small number of corgis (only eight). All the dogs are adorable, and they all belong to Amazon employees.
Cute dogs a side, Amazon has turned the page into a recruitment tool as well as a marketing meme which is bound to go viral.