A cereal bar in case I get hungry - No-one would like to be with me if I'm hungry, I get cross and agitated. So a quick nibble on my snack and I am fine!! .....
A portable black hole! It folds up and when you're stressed you take it ou, unfold it, step into it it and all time and space is void for the time you're inside. No gran should be without one! I'm thinking of setting up a company to market them.
Just about everything others have mentioned ( no wonder my bag is so heavy) and ever since a violent stomach bug a few years ago I always have a pair of emergency knickers. Have never need to use them but I do like to know they are there!!