I only travel domestically, but here's a few other things to consider:

DVD's & CD's

At least two liters of water - you've got to stay hydrated, and the severe dryness of the cabin goes against you. If you drink airline water, make sure it's bottled.

Sweatshirt in case it's cold

Change of clothes and toiletries - you never know when you'll be seeing your luggage for the last time.

Food. I prefer Trader Joe's various trail mixes.

Enough fast-reading trash novels to pass the time.

Ear plugs - makes sleeping easier when you can tune out the engines and the background conversations.

Sunglasses - also helps the sleep.

Prescription decongestant - sometimes one's ears have a hard time on rapid descents.

Laptop - mandatory - I can concentrate on an aircraft like nowhere else. I get more work done on a four hour flight than I can do all week.