My biggest quick-snack-grab is mixed nuts. I hate paying the price that stores charge for mixed nuts though, so I mix my own. I go to Dollar General and buy the following items:
2 cans cashew pieces ($2.25 each)
2 cans roasted almonds ($2.75 each)
2 bags (6 ozs ea) pecan halves ($2.50 each)
1 can peanuts ($1)
1 bag of peanut, sunflower seed and raisins mixed ($2)
1 box raisins ($1 to $2)
Then, I get out my great big Tupperware mixing bowl (or a big roasting pan would work) and I dump ALL of these into it. I don't use quite all the raisins, but I use better than half to 2/3 a box. Make sure you rub them between your hands to seperate them a bit. Once it is all in there, tumble it around with your hands to mix it all up and then pour it into the nut cans or some other container for storage till eaten. As there are a couple items in there that don't come in cans, you'll have to use some sort of container OR save cans from the previous batch... I have a big plastic container from mixed nuts that I rewash and use for the overflow once the cans are all full. For about $20, I have no less than 6 to 7 regular nut can sized cans of mixed nuts. You can use ANY nuts you like. You could even add walnuts, macadamias, pine nuts, soy nuts, etc. You could add other types of dried fruit if you prefer those--berries, apples, etc. I just like raisins and they are cheap so keep the cost down. You can bag an ounce of this mix up in snack sized ziplocs or just get a handful out of the can when you want some. BUT, don't sit down with the open can as it is SO easy to eat half the can!
Nuts are a great source of healthy fats! But, fats are higher in calories, so the total can add up quick if you overdo it!