I have always enjoyed reading. Books were under the Christmas tree every year. When I was little, my grandmother took me to the library once a week. I am not interested in declaring a "one true favorite" for everything, so these are some of my favorite authors and books.
I suppose this isn't an original choice for a nerd's favorite author, but I can only be true to myself. The Hobbit and The Lord of the Rings mean so much to me. That has as much to do with the stories themselves as the fact that they were something I shared with family growing up. I got to The Silmarillion later in life, which is for the best, and I enjoyed it. Tolkien's world is so rich and interesting.
I have a long-term, in-progress read of Tolkien's History of Middle Earth books. They are interesting, with footnotes and explanations from the author's son and posthumous editor, Christopher. I honestly wonder how the man himself would have felt about them, published as they are. I suppose that's academic.
I find that fewer people know about Zelazny. As I imagine is true with many of his fans, my first love with Zelazny is his Chronicles of Amber series. I think about the Pattern, Logrus, and walking in Shadow at least once a week. I've reread the Amber books multiple times, and have enjoyed quite a few of his other writings. Lord of Light is perhaps his most famous book. I've read that one once, and will return to it one day.
Zelazny writes such lovely prose. It's a pleasure to read his words. I've read some books that were written in a style that served only to get through the plot points--that's fine, and people like it. I figured out that I don't, when I thought "This reads like someone disinterestedly describing what they see while watching someone else play a video game." Zelazny is the author that comes to mind when I think, "Well, what is it that I like instead?"
To erase any doubt over my status as a washed-up hipster, I started reading Martin's A Song of Ice and Fire series years before the TV series started production. That's not especially relevant or interesting, but old people like talking of meaningless timelines. They were the kind of books that I stayed up too late reading. I remember I was on a vacation in another country, with all the excitement and opportunties that entails...and I definitely read one of the ASoIaF books into the wee hours a night or two because I was so enjoying it.
I ended up reading The Ice Dragon, a children's book, as an adult (not that long ago, as I write this). It's a great little tale and I think fantasy fans of any age can enjoy it.