I'm currently reading Boudica, Dreaming The Eagle by Manda Scott. It's part 1 of 3 and is set in 60 AD Britain. Clans, spirituality and battles. So far it's pretty good.
I can't name a favourite as such because I've read countless books. I always have a book on the go and have done for over 20 years, so the pile is pretty huge.
Some that are memorable are Henri Charrieres autobiography 'Papillon', 'Lady in the Lake' by Raymond Chandler, I love his style, and although he's not to my taste these days I remember enjoying Stephen Kings 'It' a lot and I really enjoyed Bram Stokers 'Dracula'. It's pretty corny but such a classic and a fun read.