i have the same problem coming home from work all the time. i started keeping canned fruits like pineapples and peaches in the pantry for such nights. you can also just make a simple sandwich. i usually go with brie cheese/spinach/tomatoes or avocado/vegenaise/sprouts. those are both pretty healthy, taste good, don't make too much of a mess and hold me over until morning when i have more time to cook.