These days, most folks don't live close enough to work-- if they're lucky enough to have work-- to walk to work. But walking, as opposed to driving, whenever possible is both frugal & a component of self-reliance. Could you walk a mile if you had to? A related thought: get a bike (yard sale). Not because it's green or healthy or hip & cool, but b/c it's an effective, cheap, low-tech mode of transportation.
Brown bag your leftovers for lunch. It's not complicated. It's frugal. Whatever you fixed for supper last night has got to be better for you than the stuff you shell out $$ for at noon. No driving just to wait in line. Blah blah blah.
Think about it.