There is a great book on the subject  which is mind expanding.
In more modern times is the Venti file server for Plan9 which uses SHA hashes as block addresses to build file contents thereby auto-consolidating duplicate file storage among other interesting features.  Which was invented by Sean Quinlan and Sean Dorward at Bell Labs (both now it Google iirc) and later maintained by Russ Cox who you may know from go-lang.
You remember things by contents, then all the contents are interconnected. Brains don't have primary-key based lookup tables.