As Mentioned previously, Hardboiled eggs are excellent quick snacks.
As I cook all my meals (up to 6 a day) I don't snack but eat every 3 hours or sooner. Lean smoked Ham with some low Fat cheddar shredded over a bed of letuce with low fat dressing is a good FAST meal.
"The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents... some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new Dark Age."
-H.P. Lovecraft