We did this w/a family on the bus. I wish I knew the title of the book ... but maybe someone else does. Anyway, they had this book w/a zillion questions. Things like "How long is the Nile River?" and it lists choices. Each gets to guess the answer and then you reveal the answer. It was the neatest book b/c it was filled w/tons of fun, interesting and educational questions! I thought I could remember the title, but forgot it the instant we set foot in the MK. I thought "What a fun way to pass time!"
We play "guess it" ... sort of like 20 questions, but you ask as many questions as you want to guess what the person/place/thing is. We usually do characters (movie, Disney, books). DS loves this game and it's always fun. We also play "Right now, in MK, someone is ..." and we name things that someone could be doing (waiting in line at Buzz Lightyear, about to plunge down Splash Mountain, eating ice cream). We each get to decide what someone in the parks is doing.