There's no telling what you'll find, in all languages, from all eras, from magazines to music to movies to games to books, maps, ephemera, junk mail.
Ted Nelson kept all his junk mail, for some reason, and now it's fascinating. Old computer product ads from the 60s and 70s, well before personal computing was really a thing. Everything changed, from the nature of the products to the nature of the ads.
https://archive.org/details/tednelsonjunkmail
see also: old issues of Next Generation magazine (half serious tech, half gamer bro, I love both sides of it)
Byte Magazine; Japanese MSX magazines. Old cookbooks. Wargaming magazines. Old books in general on everything from how to write shorthand to ... whatever you want.
Archive.org and Wikipedia are the two best places to get lost on the internet.