I think people are missing the point.
He is not looking for alternative methods of storing and taking his food to work as that problem has already been solved by buying the esky/bag that he wanted.
He is looking for food suggestions that do not need heating up that he can now put in said esky/container.
I personally do not like eating cold cooked food, ie cold spaghetti, or cold chicken and rice etc etc, so for me it would be protein shakes, sandwiches, canned tuna, wraps, nuts, beef jerky, fruit. If I had microwave available, the list would be endless, chicken and rice, steak and rice, pasta, spicy beef mince, left over dinners etc etc