Can't think of anything other than board games, Chess, puzzles, etc. But we have a few travel games that might work...
Stories: One person starts a sentence, and says a few words, and stops. The next person picks up where they left off, and says a few more words, and you go around the circle, with each person adding to the story. You don't have to finish the sentence, or you can say a fair amount. Can get pretty funny.
Nursery Rhymes: Seriously... Take turns reciting nursery rhymes, and see who wears out first. Can do this with folk or silly songs, or other things too.
Acronyms: We do this driving down the highway, from the letters on trucks or license plates, but you can also make up a bunch of three letter initial sets and put them on slips to draw out at random. You take the sets of initials and think up silly things that they stand for - like CNC: Chickens Need Candy. It is a great vocabulary builder, as well as pretty funny. We always run with one as long as the kids are still coming up with new stuff, move on to a new one when they have milked the first one good!
Come to think of it, our family plays Charades sometimes too, on lazy days at home, and the kids always love that.
You can also throw a "homemade party" any time. The rules are that everything has to be made from ingredients and materials on hand. No matter how poor we are, we can usually come up with a special menu, even if it is just homemade tortillas crispy fried and made into nachos, homemade donuts, or something else fun.