I keep cans of high-quality soup, crackers, single servings of fruit and applesauce, and packets of tuna in an unused, locking file cabinet drawer, and a big latte cup to to nuke the soup in, with my clean socks and skivvies. The local convenience store is my source for mayo, onion and relish packets for the tuna that require no refrigeration. If I have good leftovers, I can bring them on on an as-available basis.