This question seems to divide the room. Some love to re-read, others say it's a waste of time, since there are so many books out there and life is so short.
Personally, I'm very much in the re-read camp. In a lecture on Dickens, Nabokov said that you must "surrender to Dickens' voice," and I think that's the key. All the writers I re-read have a distinctive and comforting voice. When I pick up P. G. Wodehouse, for example, or Douglas Adams, it is unmistakably them. Same goes for my other favourite writers– Aldous Huxley, Anita Brookner, Bertrand Russell, Robert Graves, Virginia Woolf, etc. In many ways, re-reading them is as comforting as meeting up with a beloved friend.
I also read out loud. I suspect I developed the habit because I wanted to bring the author's voice alive. When you think about it, a book really is a kind of miracle. It's as if the soul or mind or consciousness (or whatever word you choose) of that dead author is in the room with you –especially when you read them out loud. One of my favourite books is Patrick Fermor's A Time of Gifts. But I don't read it for the content. I read it for the pleasure of his company. I've re-read that book so many times now it's like I know him.