If you do one thing over the weekend to help make the week ahead easier, do this: make a dozen hardboiled eggs and peel them all. Yes, peeling a dozen eggs at once might take you fifteen minutes or so, but then it's all done and won't have to think about it again all week. And look at all the lunches you'll get out of it:
You really can't go wrong with a classic egg salad sandwich, and you can make it in any flavor you like, with whatever bread you like. If you're worried about your sandwich bread getting soggy, just pack a container of egg salad and a couple slices of bread separately. When you make egg salad for your sandwich, make enough to use again for lunch tomorrow.
This may become one of your new go-to lunches: layer a jar with arugula, smoked salmon, and egg salad (any egg salad recipe will work here-use the same one you made for your sandwich yesterday). You'll be the envy of the office.
Mix things up in the middle of the week and pack yourself a desk picnic: package up two hard-boiled eggs, whatever cheese or cured meats you have on hand, a slice of bread or some crackers if you like, and some crudite or fresh fruit or perhaps half an avocado. Make sure you have a little olive oil, salt, and pepper, on hand. Come lunchtime, just slice open those eggs, drizzle with oil and season to taste and eat them with whatever else you packed. It'll be almost as fun as a picnic in the park.
The classic chopped salad is perfectly packable, so long as you don't dress it until right before you eat it: pack the dressing in a separate small container to bring to work. To preserve the freshness and nice green color of your avocado, make sure to toss the sliced avocado in plenty of lemon juice before packing it for your lunch.
You can slice a hardboiled egg or two into slices and layer it on top of some bread with whatever else you fancy and you'll have an amazing lunch. Or you can follow this recipe which features a tomato basil salsa and plenty of arugula: just make sure to pack the components separately and assemble the sandwich at your desk.