Sometimes, when my stomach is feeling touchy but I need something quick, I'll eat a few olives. They're nicely low-carb and tend to settle well, aside from the health benefits.

I try to keep fully-cooked sausages on hand (brats, kielbasa, whatever) as something to grab in a hurry - I don't mind them cold and they're easy to handle while driving or whatever, especially if you wrap one end in a napkin.

Seems like nuts are a "bad guy" on here, but I find them handy, too. And, as someone else mentioned, cheese and cream cheese stuffed celery are easy and quick. Good luck! My mind still boggles occasionally, too, though it's slowly becoming more of a boggle at other people's shopping choices than mine. (I still have a really hard time swallowing mayonnaise even though other fats don't bother me.)