It consists of mostly hobbyist magazines, religious texts from at least 2 different religions that I never was a member of (for reading about them), weird dated textbooks and educational books from the early half of the 20th century ("A first electrical book for boys" is among my favorites). A 6th grade reading text I got as a gift when I was in 2nd or 3rd grade, a few books from my childhood, a book on cool things like dinosaurs, and all kinds of scientific study stuff, old manuals for programming assembly on CP/M, printouts of all kinds of amusing things like scripts to log into bbses and check my email, stuff like that. There's an actual copy of a magazine specializing in users of DOS in the pile somewhere. One of the articles debated the utility of defragmentation, talking about all the bloat in DOS 6.22.
I just thought that was awesome.