The Sam Vimes and Granny Weatherwax books in Discworld by Terry Pratchett and frequently as much murder mystery as they are fantasy and I re read Pratchett every year. I still love Sherlock Holmes, although it's in a different way now than it was.
I love Ben Aaronovitch (although I have to check how to spell his name every damn time) and Jim Butcher. Mira Grant writes badass zombie/journalist/apocalypse fiction.
Guilty pleasure: Janet Evanovich's Stephanie Plum series. Yes, they are the same book over and over after about book five, but who cares? They're fun.
I get a lot of re-read pleasure out of Pride and Prejudice (not so much Austin's other works, but P and P is awesome).
I just recently discovered The Expanse series by James S. A. Corey, which appears to be crack in the form of a series of space opera books.
I occasionally get asked when I'm going to read (or write) a 'real' book (meaning literary book). I'm yet to thump anyone for asking but it's been a near thing sometimes.