The Tail Section: Excellent site for still frame photos of key scenes, along with some good analysis. But… beware of spoilers!
Sledgeweb’s Lost… Stuff: Pretty good site, but again beware of spoilers. I use it mainly for the Timeline section, which is an incredibly detailed breakdown of “how long since…?” for almost anything you can think of (pre- and post-plane crash).
Door Map from Episode 2.17. A nicely cleaned up version of the diagram Locke saw while pinned under the lockdown doors. No spoilers.
Lostpedia: The wikipedia of Lost information. Quite a comprehensive site, but beware of spoilers!
ThEmIsFiTiShErE: The Misfit offers his whacky commentary on “Lost”. Is he a nut-case or a clever insider? Careful, though, possible spoilers.
She also made a comment about getting together with her mom and his father, or something to that effect. Obviously the non-crash timeline changes start earlier than just Flight 815. Hurley goes by his given name, Hugo, and is happy and lucky. Not everything is different, though – his supervisor Randy is still a dick. I wonder whether John actually has a relationship with his father in the non-crash timeline – and if so, how did he end up in the wheelchair in that timeline?
Sawyer: “I don’t care if you’re the ghost of christmas past!”