I've been doing some research into some different well known western literature, and I see a lot of it reflected in One Piece. Some of them are already known, as seen on the trivia pages, like how the original members of the Blackbeard Pirates might be a reference to The Adventures of Baron Munchausen. The recent colorspread from chapter 604 is a reference to one of the stories found in Grimm's Fairy Tales. Usopp's name is a reference to the set of stories known as Aesop's Fables (and Elbaf is fable spelled backwards). I think that Coribou looks like Humpty Dumpty and that his crew look like Tweedledum and Tweedledee from Louis Carroll's Through the Looking-Glass and What Alice Found There. Impel Down's interior design (excluding levels 5.5 and 6) was taken from Dante Alighieri's Divine Comedy. And, the icing on the literary reference cake, the base of the storyline of the Skypiea saga appears to be based on the novel Sky Island by L. Frank Baum. This last one blew my mind when I figured it out. Look it up if you don't believe me. Personally, I love when there allusions or any kind of references like these in the manga. They are my Pandaman, my Easter Eggs.
Now, I bet you're wondering, "Why is this nerd writing this?" Well, to answer, I issue a challenge to all who read this, find other possible literary references like I have here, and provide solid comparitive evidence to back up these claims. I don't want to see the phrases "sort of", "kind of", or any of their derivations in the comments. Here's the kicker, I've found other references that I didn't list. Let's see if anyone can find one I missed. If you think this sounds like homework, then tell me, what kind of school do you go to where references in One Piece and One Piece itself are classified as homework? If I could write an SBS question, I would ask Oda to list his favorite western authors. You have been challenged (hopefully some will accept...), the rest is up to you.
Or, if you think that's too much, then give me any reference to western culture (both past and/or present) found in One Piece, and I'm putting Chapter 572's title, The Times They Are A-Changin', on here already, so I don't get thousands of responses for it (sorry, otherwise it would be too easy).