What are your must-have items for long flights?

I've got a long flight coming up and I'm actually trying to prepare this time instead of just winging it. I still have a lot to do after I land, so I really want to get some sleep during the flight. Right now I've got my Sony XM5 for noise, eye mask to block out light, and a pair of dr woof compression socks for comfort.

I'm wondering if these are enough or if I'm still missing some essentials. Any suggestions?