Choosing snacks that actually prevent the late-afternoon vending-machine run

At about four in the afternoon I get hungry enough to buy whatever is nearest the office register. A piece of fruit alone doesn't hold me until dinner; a pastry does, but then I feel sluggish. I'm testing snacks that combine something filling with something I actually look forward to: yogurt and nuts, cheese and crackers, or hummus and carrots. What do you bring that survives a desk drawer or office fridge and genuinely stops the vending-machine visit?