Holy cow! 18 replies already!

Wow guys, great suggestions, thanks so much!!
The trip report is a great idea, I think I'll do it! I actually made this trip last January, but I went by myself, packed very little in my carry-on, and had strep throat BAD, so have little memory of the flight, hence no report.
I was a zombie on the way over (thanks to the cough syrup!), and I had an empty seat next to me so it actually wasn't too bad, but the flight home was 100% full (full of returning American students, it appeared, along with Jerry Springer in First), and I was so cramped and when I WAS able to get to sleep I'd wake up every hour, and it was torture!
I've still got some of the stuff from the amenity kit from that trip like the eyeshade, footies, earplugs....(actually that's kind of icky, why do I still have those??) plus I snagged a discarded kit from Business class while de-planing (everything in it was still sealed...wow!) so I've got the lip balm, the face spritzer, etc...
I figured I should bring lots of snacks...I already mentioned I have a 12 year-old son...need I say more? So, what food travels well, and doesn't take up much space or weight? (Besides trail mix!)

Also, I plan on having one carry-on bag each, plus a smallish backpack for each of us, as the "personal item". Does a sack of snacks/food count as extra?
Re: Gameboy/batteries, I've already been "informed" by my son of the fact that he'll need extra batteries. He's more concerned about that than the fact that we're goin' to freakin' Australia...
Feebs: Actually, I won't be spending any time in Sydney (tho I had a great time there last time). I'm going straight on to Tasmania, to Hobart. I'm getting married
Crossword puzzle book...excellent...
tweezers, nail files, clippers, and corkscrew. - Duly noted....What, no scissors?
Thanks again for all the suggestions!