I like to read through old RPG books and zines for inspiration for my games, and lately I’ve been enjoying the Arduin Grimoire (https://en.wikipedia.org/wiki/Arduin), one of the earliest 3rd-party zines (coming out during the initial run of OD&D). It’s filled with a bunch of unique ideas (some better than others), entirely too many charts, and is very much a product of its time, but there’s something about its “raw”-ness (and its variety) that I still find appealing.