I don't bother sleeping.

[a] Can't sleep on planes anyway
[b] short 1-3hrs of semi-sleep make me feel far far worse than being deprived of sleep.

If I'm reasonably active, lack of sleep isn't really a problem. It's all the sitting around doing very little that is boring and you start losing the will to stay awake.
I'll always go to bed at a normal hour wherever I am no matter how long I've been up for - I always feel better in the morning and it's natural.