The Independent Order of Odd Fellows apparently has some interesting human remains collections. This was supposedly done as ritual theater, confronting initiates with the occasional memento mori. But they could last a long time:
[A]n electrician fixing up a former lodge in Warrenton, Virginia, found one hidden in a recess in between two walls. “You could see the rib cage and the sinew,” he told the Washington Post at the time. “It was like a Dracula movie.” In 2004, a group of girls in Houston, Texas, stumbled on a casket full of bones during cheerleading practice. There have been similar finds all across the country: in a basement in New Jersey; a crawlspace in Pennsylvania; a cobwebbed wardrobe in Washington State.
Infocult is always there when you look for it, peeping forth like the skull beneath the skin.