When going out for the day I often take Slimfast milkshakes. They are a nutritionally balanced meal replacement and quite tasty (especially the coffee flavour). If you are underweight and worried about people seeing you with 'slimming' foods the labels are easy to remove! I also find them easier to take than soups etc on days I am not feeling too good.

That's a good idea Sheila. We always kept small ring pull cans of ambrosia rice pudding in the car as they are also a good instant filling soupy food and are not too awful eaten cold if despreate.