Books. I diiiiiiiiiie for used book stores and can spend hours in them! I'll buy from ebay, amazon, chapters, used book stores, library sales, etc.
Only non-fiction books on:
-archaeology
-anthropology
-world history
-medieval history
-WWI and WWII history
-geology, rocks, fossils
-geography
-dinosaurs....of course
I will also collect old issues of National Geographic, Discover, Archaeology, Scientific American, Nature, and Time magazine.
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