If you are a Star Wars fan then you might enjoy this writeup about the continuity of the story. When we watched the first Star Wars movie we made assumptions about what preceded the story. Eventually, George Lucas let us see the back story. Now, Keith Martin has laid out exactly what that back story means to the first, er fourth, movie and how things change in light of those revelations.
Ironically, we watched 4 last night. The original, Han Shot First Dammit version, which I had to get from my friend the internet because Lucas sucks.
Anyway, it was good.