My collections of stuff as a kid evolved into collecting extensive research and studies about the use and making of herbal medicine, plant classification, etc.
Also, since becoming a mom, I have extensively and obsessively researched things like birth, breastfeeding and circumcision and tend to info-dump about all of those topics.
I always have room for a newest fascination, though. I love genealogy, I have a tree with thousands of family members and photos, personal stories, personal info dating back to the late 1300s so far.
I love old cemeteries because they are very peaceful and usually have lovely statues and lots of history. My husband, my daughters and I love to hang out at old cemeteries and have a picnic or something. Family thinks we're totally odd but whatever.
I do love studying about dinosaurs, cryptozoology, ethology, genetics, etc but I don't infodump about those as often but I do research obsessively; I just don't talk about them much.