Cold Meat Salad is a good one, i spicy it up and ensure i have pickles with it, such as pickled onions, pickled red cabbage, kherkins etc.
Omelettes can be made in advance and heated up in the microwave.
Hard Boiled Eggs
Quorn Sausages with tinned tomatoes
Bacon Sandwich (i cook it before and heat for 40 secs in microwave)
Homemade soups are good