Most of my Paleo meals have been so hearty, I haven't needed many between-meal snacks. Getting stuck without handy food when I am shopping or traveling leads to the temptation to eat whatever fast food is nearby. Sometimes I keep an apple or a banana in my purse, although it occurred to me, Kroger/Walmart people might think I have stolen it. (I have such a guilty mindset.)
Only a few weeks into the Paleo Diet, however, I have a pretty good list of 100 or less calorie snacks, treats or munchies. Remember: no grains (bread, chips, wraps, etc.), dairy (milk, ice cream, cheese), soy (edemame, tofu, most dairy replacements), legumes (peanuts or beans), or a few other Paleo restrictions. Some are portable; some I need to be at home with a fork and table handy. Hundreds of 100-calorie snacks are listed on the internet, but these are the ones I actually try to have on hand and eat. Enjoy, and add your own favorites.
SEEDS AND NUTS: About 1/4 c. of Sunflower seeds, pumpkin seeds, pecans, walnuts, cashews, Brazil nuts. Brazil nuts are high in fat, but only about 3-4 will fit into a 1/4 c. measure anyway. Any non-butter or sugar-seasoned variations should be fine.
BERRIES: About 1/2 c. of raspberries, blackberries, blueberries, or cranberries, even with almond milk, is good. You can have a whole cup of strawberries since they are mostly water. Dried blueberries and cranberries are pretty easy to find in most snack aisles. Be careful-read labels if you buy these in a snack pack: they probably have added sugar.
SOLID FRUITS: You can have a whole medium apple, pear, orange, tangerine, banana, bunch of grapes or other fruits that are easy to find in the stores. Strict Paleo proponants say they must be organic, wiped clean of wax, etc. I just wipe them off, peal if needed, and eat one. If you slice or chop these, you will end up with 1/2 to one cup of fruit, and they are good mixed in a fruit cup, too.
JUICY FRUITS: Peaches, mangoes, papaya, necterines are great, but 1/2 c. usually has 100 calories. These (and bananas) are very easy to add to smoothies and add great sweetness, but the calories add up if you drink a whole blender-full, which I do for a smoothie meal.
RAISINS/DRIED FRUITS: Including craisins (cranberry raisins), and all sorts of fruit trail mixes are handy; just limit to a palm full if you want to stay about 100 calories.
MEATS: and fowl and fishy things, about 2-3 oz.. Amazing how good a leftover slice of roast beef can be and can make me feel more satisfied than raisins sometimes. Seasoning salts are basically calorie-free (watch the salt if you need to), and can add more punch to each bite.
ALMOND BUTTER: and cashew butter, sunflower butter, etc. are ok but peanut butter is not. If you want 2 tsp. of almond butter, eat 1/2 the amount of fruit for 100 calories.
UNLIMITED VEGGIES, ETC.: celery, carrots, cabbage, salsa, picante sauce, veggie soups (no potatoes or corn), jimaca sticks (you gotta try these), mustard, vinegar--adding these to a snack or meal really adds bulk and taste, but very few calories. If you ate a pint (2 c. usually) of these, you might have a problem, but you can usually eat all you want of these.
JUICES: orange, peach, apple, grape, cranberry, tomato, etc.--usually 1/2 c. is about 100 calories. Unless you make the juice yourself, you will probably buy them at the grocery store like I do. Read, read, read those labels. Fruit punches or "peach drink"-type choices are usually loaded with sugar and calories. Even "100% Fruit Juice" can be tricky; sometimes that just means no artificial fruit juices or flavors are added, but lots of syrup can be in there. If I end up with some sweet juice as my only choice, I add club soda, sugar-free ginger ale, or just lots of crushed ice.
MISC.: a small baked apple with just a touch of honey or sugar, plus cinnamon and a little olive-oil based margarine is about 100 calories. 1/2 c. fruit smoothie (no dairy), 2 small dill pickles, or 1 egg fixed about any style are each 100 calories. 1/20th of a pie, which breaks several Paleo rules, is 100 calories.
Snacks or tiny meals may get you through a tough spot, if you plan ahead and have food ready to eat. Leave that sleeve of crackers, hunk of cheese, or candy bar where they belong--in somebody else's tummy. You can do it!