I do.
If I can lie down, I sleep. The one time I took business class flight to UK, I slept really well - also the one time I took a half full plane to Dubai and could lie down on empty seats. Was wonderful.
Unfortunately my budget doesn't stretch to business class again and Ive never since been on a flight with empty seats.
Even without lying down, I can sleep intermittently on long flight, say, an hour here or there - neck pillow, earphones with relaxing music.
Have never taken sleeping medication in my life.