A good book to read (several if carrying an i-Pad or Kindle) and some salty and sweet snacks would get me comfortably through several hours. Internet access would easily kill a few hours. I always have my laptop.

And I always have tissues (substitutes as tp) and some other comfort items on board.

There are far worse situations than sitting in an airplane for a several extra hours - that is one which does not worry me. It would be very irritating.

Remember to pack the earplugs -- well worth the fraction of an ounce.