You aren't insane....just adventurous

There will be movies and a kids channel on the plane. Also magazines etc. Does she like drawing - you could take some crayons. Also I found this awesome thing at Melbourne Zoo the other day although it is a little bulky - it is a travel table for kids with a magnetic scene set (a jungle scene and you can place the animal magnets around) and also has a drawing set. Cant wait till DS is old enough for it.
You could also take an old camera for her or an old mobile.
Take no-preservative treats - to avoid hyping her up too much.

HTH! I am sure it will all be worth it.