I’m fighting the battle of the middle arm rest. The man next to me, a very big man who doesn’t quite fit in his economy class airplane seat, is spilling over into my space. We’re shoulder to shoulder, actually touching, but I refuse to yield. I won’t sit folded up like a pretzel for three and a half hours. Air travel fascinates me. A group of people who don’t know each other are crammed (for those of us denied the luxuries of first or business class) together in a box suspended 38,000 feet in the air and forced to get along with each other for hours. You sort of have privacy. You stake out your territory with your invisible walls, your bag under your half of the under seat space, your laptop or e-reader or book (yes, people still take these on planes) in front of you like armor. You may wear headphones or earbuds to signal you want to tune out everything around you and be left alone. Some people sleep (or try to in those horrid little coach seats). Some jerks use their electronic devices to listen to music without using headphones. (Yes, you are a jerk if you do this. The entire plane does not want to hear your tunes. Use headphones or earbuds.) Some people chat with their traveling companions. Some people chat, or try to, with the stranger sitting next to them, even when it’s obvious (or should be from the book/headphones/lack of eye contact/snoring) the stranger next to them isn’t feeling talkative.I write. (True confession, tonight I slept. It was 11 pm, I’d been up since 5 am, and I had to be back at work the next morning at 6:30 am.) I get a lot of writing done on airplanes. I have an uninterrupted block of time. Excluding mister music-with-no-headphones, there are few distractions. Just enough going on around me to act as white noise. I’m surrounded by inspiration if I’m stuck for a character: her nose, his ear, his hair, her outfit. Maybe even my next literary murder victim. Hint, hint, Mr. Music.And, yes, I won the armrest battle.What do you do on airplanes?