[Sadie's Mom]

When they "hide things", they're not really hiding them, just putting things in to see how people are paying attention. Like the numbers will be in the episode somewhere (for example, the numbers were on the top of police cars in one episode) And in flashbacks, tehy will show how the people relate to each other. You might see one of the characters in the background of someone else's flashback. Or for examle you might see a relative of one of the characters in someone else's story (Sayid's girlfriend was in one of I think Locke's stories, Kate's mom was in someone else's story). They just put stuff in there to see how you are paying attention & so to show how everyone on the island relates in some way. It's really cool. I'm so bad at spotting them. But after a new show is on, one of our radio stations does a whole segment on what the "hidden" things were for the night. I'll try to find a web site that lists some of them. I haven't watched the show since the season finale, so I can't come up with any more examples, but I'll try to find some.