What's Your Favorite Form of In-Flight Entertainment?

With the weather getting warmer and the days getting longer, I've got Summer travel on the brain. For me, travel often means sitting for hours on a plane, reading a book, or getting sucked into whatever movie is playing over the airplane's system. (Hey, next time I'm stuck on the tarmac, maybe I'll try Twittering with customer service like our Cotorture girls did!)

Now, some airlines have options for purchasing movies on flights, but when I asked you about it, most of you said you weren't sure you'd be buying. So, what is your favorite way to entertain yourself on a flight?

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