Make a plan..
I agree with Dan, that flight shouldn't take THAT long unless you do a lot of circling over the airport.
I've flown back and forth from Washington DC to Germany many times... (try moving your belongings 140 lbs at a time).

That's an 8 hour flight, approximately.. not to mention all the hassle of airports, security and such. I wish my laptop had a DVD player because that would REALLY take the time out.
I just use the Boy Scout motto 'Be Prepared'. I make sure I bring ANYTHING I might need. I know I've been on a plane a few times before and not felt too well, that SUCKS. So I have medicine for headaches (hangovers), motion sickness (although I don't get motion sickness) as well as PLENTY of entertainment. I bring a DISCMAN and tons of CDs that I usually burn before I leave. I also bring car magazines.
If you really are having a problem, try this. Make a plan. I'm a teacher, I make plans all the time. Try to plan your time out. Remember to divide your time up into sections. Maybe read for the first hour. Play Gameboy for the next hour, or whatever games you have on your laptop. Third hour, listen to CDs or watch a DVD movie. Remember to break it up. Attention span usually lasts about 30 - 45 mins before it needs a change. Between activities, walk around the plane. Get a bit of exercise. Take another hour and write a list of all the things you need to fix on your GN... (this took me a couple of hours)

In the time that it takes, that'll help you gauge how much longer to go and help time go by. Also, as any teacher will tell you, NO PLAN EVER GOES AS PLANNED. You'll have problems following and revising your plan. Remember, the meal will come and you'll have to interupt your plan. The person next to you may strike up a conversation. Your plan will have problems. So much so that you'll be mad that you're already there and didn't get everything done.
Hope that helps.