Shout-Out: "Funky Bones" is located at Indianapolis Museum of Art where Sarah Urist Green, aka The Yeti, is Curator of Contemporary Collections. The author's wife had a major hand in bringing the sculpture to Indy.
Shrug of God: John Green has had to do a lot of this to fans who want to know what happened to the characters before/after the contents of the book; this becomes somewhat humorous in light of the fact that there’s also a significant in-universe example where Hazel and Augustus ask Van Houten what happened to the characters of An Imperial Affliction and he tells them he doesn’t know.
Hey, It's That Guy!: Much has been made that Shailene Woodley (Hazel) and Ansel Elgort (Augustus) will play a couple in TFiOS and siblings in Divergent.