Some airlines also prohibit carrying matches or lighters in hand luggage.
If you or your family take any prescription medications, take those in your hand luggage in their own, marked bottles.
In the US, security routinely checks all electronic devices - mobiles, CD/MP3 players, etc. - and sometimes ask the passenger to switch on the device. Ditto laptops.
I always take gum or boiled sweets to suck or chew during take-off and landing as well.
A scarf, sarong or pasmina makes a good blanket, shawl or head covering. Can even be used as towel in emergencies.
Comfortable shoes that are NOT flip flops but can got out of off easily.
Sox so I can take off my shoes in flight.
A stretch band to exercise my feet and lower legs on longer flights to prevent DVT.
Water - a must!
Baby wipes
Extra clothes
Toothbrush and toothpaste
Light perfume or body scent in a spray bottle.
Vaseline - moisturiser, lip balm, hair smoother, eyebrow tamer