To-read list
Below is a list of all the recommended books Mortimer J. Adler and Charles Van Doren's "How To Read a Book". This is the widest-ranging list of historically signifcant western literature I'm aware of, as it includes scientific works, which most similar lists omit.
I don't read frequently so I'm not setting my goal to read every book in the list (and the creators of the list also specifically advise against attempting that), but I want to include classic books among what I do read, so I'm using the list below simply to have an easily accessible reference when considering what to read next, and save the trouble for anyone else who wants to use the list (You can also download the image summary or orgmode source). For the sake of pragmatism, I will mark any vague listing (such as "works", "essays") as "DONE" once I've read some of their most significant writings rather than attempt to tackle their complete writings: