Cheaper than buying protein bars and with less sugar too.

Ingredients:
1 cup rolled oats
1/2 cup nut or seed butter
1 1/3 cups low-fat milk
1 1/3 cups vanilla protein powder
1/3 cup dried cranberries
2 teaspoons finely grated orange zest

Grind the oats into a fine powder in a blender, add butter and milk. Blend it all together until mixture is smooth. Add the protein powder and blend again. Stir in cranberries and orange zest. Transfer mixture to a baking tray. Place a large piece of wax paper on top of the mixture and use it to spread and flatten the mixture evenly. Cover and refrigerate overnight until very firm. Using the liner, lift the mixture from the pan and transfer to a cutting board. Uncover and cut into eight bars.

Each bar provides:
20g protein, 15g carbs, 5g sugar, 11g fat, 3g fiber

Keep them refrigerated and I wouldn't advise taking them to the gym in your bag but they're great to nibble on if you get peckish at home and don't want to be tempted by chocolate bars or whatever. Also a tasty way to bump up your daily cals.