We always play I Spy. You know...I Spy something brown and then everyone else has to guess what it is, then the next person goes, etc. Also, we play the alphabet game. That's where everyone goes in order and has to name something they see that starts with the letter your on. If your family is waiting at a bus stop the first person might see "Ariel" on someone's t-shirt and then the next person could say "bench" for the bus stop benches, and the third person might say "car" if they see one passing, etc. It has to go in order of A, B, C, etc. You might have to make exceptions for X and Z. We say it's okay to use words with those letters in them, like "express" or "extra". (Zippers are always available!) If you have little ones, have them go with a sound of the letter or use adjectives.
It's kinda funny cuz we love playing these games and after we start, you can hear other families around us doing the same thing. You forget about some of the little easy things and at the end of the day everyone is tired and cranky and this really helps to lighten the moods while waiting.
Hope this helps!! Have a great trip!!!
Suzi