Okay:
All time favourite (and my nomination for the BBC's big read, for those who've heard of it) is The Count of Monte Cristo by Alexander Dumas. I've read it from cover to cover five times (which is pretty good going, if you've ever seen the size of it) and I've dipped into it far more often than that. I haven't done so much recently, but that's more because I know the book too well, rather because I don't like it any more.
Michael Strogoff by Jule Verne is terrific, too, even if the ending had me wanting to spit. It's fantastic up until the dramatic climax, and then... Ugh. I always want to rewrite that bit.
Nicholas Nickleby by Charles Dickens. I like that one rather a lot.
I'm also a Dick Francis fan, and I particularly like the Sid Halley books, Odds Against, Whip Hand and Come To Grief.
Oh, and Harry Potter of course... Yes, I was one of those sad thirty thousand people who preordered The Order Of The Phoenix on the same day its release date was announced.
While I wouldn't put it on my must have list, I also want to endorse the recommendation for Thunder and Roses. Wendy pointed me in the direction of Mary Jo Putney, and that is my favourite (by quite a long way) of the books I've read.
Oh, and two last books I'd recommend: The Fool on the Hill by Matt Ruff (a delightfully quirky fantasy novel -- not my favourite genre normally -- set around Cornell university) and The Crow Road by Ian Banks. Both these books have plots that seem very fragmented at the beginning but which come together into very satisfying wholes towards the end.
Chris (who has spend far too long reading these boards tonight and has probably doubled the number of her posts in the process.)