Cheat: Type GODHAND all in capitals on the ship to get Rikku's legendary weapon Godhand.
Audio problem: In the scene where Tidus and Yuna are conversing at the Farplane, Yuna says something slightly offensive about Tidus' mother, to which he replies, "Whoa there, that's my mother you're talking about!" Almost immediately after, you hear Yuna say, "oh, I'm sorry," but her mouth doesn't move.