I go for months on end eating carrots and humus every day. I add an apple, something salty, chips or crackers and a cookie if I'm really rolling in time. I pack an icepack with it and don't worry about refridgeration.
I get a tub of Tribe hummus and split it into 5 portions. I cut carrots ahead (I prefer sticks vs baby) and keep them in water, then just portion out what I need the night before. Usually the equivilent of 3 or 4 whole carrots
Can do peanut butter and celery the same way. I'm making my own humus now, but haven't perfected my recipe yet. I still splurge when my favorite is on sale, or if splurging on humus means I'll pack lunches instead of eating snack food or eating out.
I also do a lot of soups. Vegetable, pumpkin, beef and barley. I make a big kettle and eat it every day (sometimes every meal) until it's gone.
Another favorite is chicken and rice and brocolli. I put small chunks of chicken in the bottom of the rice cooker, then the rice and water, then spice. This week it was a mexican steak rub I've been trying to use up. Then I put the brocolli in the steamer tray and let it cook. Twenty minutes later I have lunches for the week ready to go. There's a microwave at work, but I often eat it cold.