If you have the facilities at your work, bring ingredients and make your own lunch. Lots of people "bring lunch", where they bring leftovers (cool - but I leave those for the Mrs. and Jr.), or Lean Cuisine (seriously? they cost like $3/ea and don't fill you up, and I usually see these folks drinking diet soda, too), or the quintessential Cup Noodles (I get an MSG headache thinking about it, and they do NOT fill you up).
So there's bringing lunch and then there's bringing lunch. I bring lunch, by which I mean that every Monday I stop by the store on my bike ride in and I buy:
Avocados (because they're cheap at Food City)
Cheese (bought maybe every two weeks, less if I remember to bring the Costco cheese from home)
Then at lunchtime I go to the kitchen with a heaping bowlful of fruits and veggies, get out my cutting board and knife, and proceed to whip up an AWESOME salad. I have cheese and fruit on the side, and I usually smear peanut butter (from Costco) onto the apples for extra protein. I dress the salad with raisins, olive oil, and red wine vinegar, and it kicks butt. It definitely provides all the energy I need to bike home, and I'm sure it makes my colon happy, too (FWIW).
Average weekly lunch-spend is about $11. For a filling, kickawesome lunch, every day.
It's also funny to get comments in the lunchroom. I'm afraid that my very basic-but-healthy salads inspire other people with guilt. I'm also afraid that when one lady mentioned this, my response (trying, of course, to not hurt her feelings by critiquing her gross microwaved-cardboard lunch) was :"Well, we all make choices."
Um. If you're reading this, lady, I'm sorry.
What I MEANT to convey was: healthy eating can be inexpensive and simple! All it takes is a little thinking ahead and the willingness to choose some extra health over some convenience! Simple, happy choices! That we all make.
I'm bad at talking, sometimes.
But you, too, can figure out a way to eat healthy wherever you are and whatever you do! It may take some ingenuity, and it will take some extra time, and it might even call for tact (whoops), but it can be done as long as you are not a complainypants.
So there you have it, now go and do it yourself.