Everyone's doing it...
1) To Kill a Mockingbird by Harper Lee. I think this may be one of the most important books ever written. It's beautiful.
2) The Watchmen by Alan Moore and Dave Gibbons. Had a huge impact on me when I was young. Helped me explore concepts about heroism, ends justifying the means, honesty... Just a great story, too.
3) The Advanced Dungeons and Dragons Player's Handbook by Gary Gygax. My first real roleplaying book it opened up my creativity in a way that has profoundly affected every part of my life since.
4) The Day of Dissonance by Alan Dean Foster. It's the first "Spellsinger" book I ever read - a gift from my sister. It was set in a world with talking animals, but they were not all cutesy - no no. The hero has to drag his otter friend out of a whorehouse in chapter 2. The book was an eyeopener for my 11 year old self. Thanks, Jane!
5) A Tale of Two Cities by Dickens. Those of you who have roleplayed with me know I'm drawn to the tragic hero. This was my first taste of tragic heroism - Sydney Carton. What a great story and a great ending with two of the best lines ever written in the English language.
6) Watership Down by Richard Adams. A book about rabbits. But not really.
7) A Game of Thrones by George RR Martin. This one was great, but the series is starting to wilt a little bit so I worry it won't end as well as it began.
8) Ulysses by James Joyce. Yes, I have actually read the entire thing. This is probably one of the best books ever written. It basically says hey, you can do whatever you want in a book. Just try it dammit. The stream of consciousness internal monologue chapter is one of my favorite moments in all of literature.
9) The Voyage of the Dawn Treader. I chose this one from the Narnia books because it is my favorite and because I like the redemptive nature of the story. Plus, the idea of sailing on a ship to the end of the world is just a great concept.
10) Mythology by Edith Hamilton. It was assigned in school and was my first real in depth experience with the Greek myths, which have a huge impact on all of us.
11) The Hero with a Thousand Faces By Joseph Campbell. If you know about Campbell, you know how important his work is to understanding humanity. Read it, if you haven't.
12) Where the Red Fern Grows by Wilson Rawls? Read this is 5th grade and it had a profound impact on me. I re-read it every couple of years.
13) The King with Six Friends by Jay Williams. This is a children's book that taught me how to be a leader and the importance of having a leader. Still one of my favorites.
14) Here Be Dragons by Sharon K Penman. Introduced me to historical fiction. Great series of books.
15) The Road by Cormac McCarthy. Great novel and incredible writing.