In college, I got used to eating all the time. I'd get hungry during class, after class, before class, late at night while studying...No wonder I put on 20 pounds. Now I'm in much better shape and go to the gym much more often than in school (almost every day, sometimes twice a day, rather than every other day), but I still have the munchies almost constantly. I try to abate my hunger by eating a large breakfast and drinking lots of water throughout the day. That definitely helps, but sometimes I still get in a snacky mood. So I'm always prepared for when I have a grumbly tumbly!
Skittles or Back to Nature cookies, are for after lunch, when I just need something sugary to cleanse my pallet. And anything else, like Cheetos or whatever else I may have in there, are for emergencies only; I don't usually eat them, but if I brought a really small lunch (or forgot one entirely), then they would come to the rescue.
What do you usually snack on at work/school?