They're books which work on so many levels, with layers of subtlety and literary cleverness and even little buried jokes. There's truly nothing else like them in fantasy fiction.
1. Comfort reading/nostalgia/guaranteed satisfaction (e.g. Mark Twain, Joseph Conrad, some of the SF greats)
2. Knowing there's more in there to absorb that I didn't get last time or have forgotten (e.g. various Neal Stephenson doorstops, biographies, history books)
3. Suspicion I didn't "get it" the first time and might appreciate it more now (e.g. not a personal example, but good summary - the famous line that "You read Don Quixote three times in your life. The first time it makes you laugh. The second time it makes you think. And the third time it makes you cry.". My personal example would be Code Complete!)
4. Plus, this being HN, straight technical books, which I reread to refresh and improve skils
The last book I reread was Kerouac's Desolation Angels, which actually for me was an interesting mix between categories 1 and 3.
- Lord of the Rings, same reason as above
- Life of Pi. The story is so good, the emotions are so real, and the air of absurdity and comedy throughout are so well done
- The Martian, it’s again such a good story and fantasy novel
- Bartleby, the Scrivener. Something about Bartleby as well as his boss spoke to me, as a young professional early in his career. I also loved the imagery of a clerical office in a Manhattan high rise in the 19th century
2. K&R The C Programming Language I've read/owned well over 100 programming books but K&R is the most beautifully written programming book ever imo. I have read it multiple times and will continue doing so.
Why? Old friends; been a long time so they're fresh again; authors that quit producing, this is all I have. That's some of 'why'.
Fiction:
Neuromancer - William Gibson
False Memory - Dean Koontz
The Mysterious Island - Jules Verne
The Lord of the Rings - J.R.R. Tolkien
Nineteen Eighty-Four - George Orwell
Non-fiction:
The Four Steps to the Epiphany - Steve Blank
The Discipline of Market Leaders - Fred Wiersema and Michael Treacy