Smoke crack and goose the stewardesses. Preferably at the same time.
Does that count for the mile high club or does there have to be more than one person involved?
But all they play is Skippy the Bush Kangaroo, Crocodile Dundee II, Australian Rules Hurling, and the Wooloomoolong Ladies Didgeridoo Orchestra plays Slim Dusty’s Greatest Hits.
You can keep flexing your legs so you don’t get deep vain thrombosis. Not much excitement in itself, but it should take up about four minutes and thirty four odd seconds of your time.
When I was 15 managed to do that twice on my way home from Australia on a Qantas flight. :o
How about a book (or two) on an MP3 and some knitting or cross stitch? You could also listen to the book while playing Soduko.
Lots of reading material, fully loaded iPod, cards, sleeping aide. Also, pack a washcloth and toothbrush/toothpaste and some face cream or lotion (I have no idea if you’re a guy). Anyway, on my trips to London, about an hour before we land I wash my face, brush my teeth etc–even if I haven’t slept a wink, it helps revive/refresh me.
You could always start a poker game-jacks wild, double or nothing. 
If you begin hearing music… boom chica chica wah wah… and the stewardess comes over and offers to check your seatbelt, then it counts. Otherwise, no.
Maybe not something you’d fantasize about on United, but if you’ve been on as many SQ flights as I have you know the feeling.
Depends on the lack of involvement I’d say if you did so in your seat with people watching you’d get credit for something. Not necessarily full mile high club membership but certainly something.
My game plan for long flights is sleeping. It generally works well for me. If I’m having trouble passing out alcohol helps.
Can you have knitting needles these days? I’m a cross-stitcher, and I had my very tiny, blunt-nosed embroidery scissors confiscated at security the last time I flew!
I always bring a book that I’ve been saving for the occasion, crossword puzzles, and the aforementioned cross-stitching.
I thought you could–I think they have to be plastic.
I don’t even knit, though I’d like to learn. I can’t imagine that long of a flight with nothing to pass the time. I need to keep my hands busy.
When I flew back from Sydney to LA I asked the pack of flight attendants for a drink that they didn’t happen to have. In a scene somewhat reminiscent of “Mister Rogers” they cobbled together a close attempt using whatever was in the drink assortment.
I went back to my seat and enjoyed. Shortly thereafter a half a dozen of them came out of the kitchen area holding a variety of drinks and I heard them discussing how to split up and find me. They had decided that their in-flight entertainment was going to be getting me potted on whatever unusual combinations of drinks they could put together.
It worked. I recall a very restful, fun flight. Took me a week to get over the combination of jetlag plus hangover.
So make friends with the flight attendants (works great because when they dim the cabin lights and the attendants are all hanging out together, you can strike up a fun conversation). Bring a book of mixed drinks. See how close they can come.
They aren’t supposed to do that on flights originating in the US. When I worked in a yarn store, I always advised wooden or plastic needs, generally circulars if possible. I never heard anyone getting them taken and that was post 9/11. Small nail clippers also work for cutting thread and aren’t confiscated, normally.
You’re welcome. This is the Straight Dope; it is what we do. 
In such situations, I have a sketchbook and some pens and pencils. Hours of entertainment!
[sub]Wish I was going to Austraila…[/sub]
Horse tranquilizers.
“It’s a book. It’s a non-volatile storage medium. It’s very rare. You should 'ave one.” – Blank Reg
Stranger
This cannot be overstated. Be nice to the flight crew from the start. Engage them in conversation when you can. Empathize with them. In the middle of the night when they come thru with 2am snacks (they always did when I flew between Oz and the States), stand up, walk to the kitchen and try and start a polite conversation.
I did that on every flight and it pays dividends. On one flight I ended up next to a screaming infant and its parents oblivious to mayhem their child was causing. I did not complain but endured. The flight attendants couldn’t move me because cattle car class on that flight was packed. So I got extra attention - blankets, pillows, food, etc. And since I didn’t whine about it, at flight’s end I was presented with full bottles of one red and one white wine from first class. It was the best they had aboard.
Ever since that flight, I still purchased cattle car class tickets but used my frequent flyer miles to upgrade to business class, with its extra room and more toys. I continued to be polite to the flight crews on those flights and always had fun. There really never were any long flights as a result.
Having gone to and come back from the US via Auckland recently, I can assure you that you probably won’t even get through one book. The airline (Air New Zealand, FWIW) had LCDs in the headrests, and a huge selection of films- everything from Casino Royale to Night At The Museum to The Wind That Shakes The Barley to Tenacious D In The Pick Of Destiny. Add to that the TV shows, sleep, meals, and staring out the window (I love the view of the earth and the clouds from 30,000 feet), and I hardly touched my copy of Lawrence of Arabia: The Authorised Biography.
I’m saving the rest of the book for the honeymoon flights next year. 
I recommend do a HUGE amount of endurance exercise just before you leave for your flight. Preferably you should run a marathon or go biking for 6-7 hours. That way, you’ll want to sleep for 12 hours straight.