If you're interested in reading some classic science fiction, but instead of selecting titles from the 100 Best SF Books you wish to confine your selections to a single author, and if that single author happens to be Robert A. Heinlein, then check out this ranking of Heinlein's novels by Heinlein-fan Kevin Drum, otherwise known in bloggoland as CalPundit. I've only read a smattering of Heinlein's short stories, but Stranger In A Strange Land and The Moon Is A Harsh Mistress have been on my reading list for some time. I think I'm going to nudge them up in the order.
(By the way, CalPundit has quickly become one of my favorite blogs, both for his intelligent content and for the fact that since he lives in California, the time-zone difference usually means that there is something new to read on his blog when I get up in the morning. That role used to be served by Den Beste, but somehow I can't seem to wrap my mind around an SDB essay at eight in the morning. Generally I have to wait until around eleven or so before I'm ready to inflict words like "Jacksonian" upon myself.)