if you have a ds or psp, that'll help kill some time but i think the best thing to do is just sleep...maybe that's just me haha (maybe listen to music?)
Play PSP til it dies out and use the back-up battery til it dies out, then sleeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeep.
sleeep, mp3, or strike a conversation with someone sitting next to you, if not ~ have fun getting bored! ^^