Antique photographs. Degaeurrotype, cabinet and imperial cards, tin types....anything dated pre-WWII, but more specifically, memento mori.
In the 19th century and the early part of the 20th century, most people didn't have access to a photographer. The photographs that we take for granted these days were almost unheard of, and some people went their entire lives without ever having their photo taken.
So, their photos were taken in death instead. Sometimes people were posed to appear alive, with the photographer painting their eyes in post-sitting. Some folks were draped artistically across couches or beds, and some had their photos taken whilst laying in their caskets.
A great number of memento mori are of children. Parents wanted a photo to remember their children by....I can understand why so many of them chose to have their babies photographed in death rather than not at all. You have to remember that this was the age before antibiotics and widespread vaccinations; the child mortality rate was astoundingly high.
Rather than being grueseome (although the ones that have painted eyes can be slightly disturbing), these memento mori are often beautifully lit and staged pictorial mementos. I like them, that's why I've started to collect them.
Now if I could just figure out WHY I like them...