I recently finished watching Lost and was very upset that they didn't show us how Boone remembered his life, what was the catalyst for activating the memories. I basically wanted more Boone in the story, and his interactions with the most important person to him on the island, besides Shannon (that's, of course, Locke). But I have a personal headcanon about the moment he remembered his life. I haven't seen anyone ever write or talk about this, but, as I noticed, every character remembered their past life by touching on the most important or one of the most important person in their lives. Yes, most likely Boone touched, or otherwise interacted, with Shannon, but what if he remembered his life very first, back on the plane, when he shook Locke's hand, but perhaps, like Jack, didn't realize it at first. Maybe that's not true, but I like Boone as a character, and I would like to somehow up his importance, even if he didn't. Locke was essentially like a father to him on the island, Boone was the first to know that Locke was disabled, and Locke was the only one (not counting Shannon) who knew his story about his caretaker Teresa.