I like Think Thin bars- tastes good, high protein (@20 grams) and lowest in sugar compared to others.
I compared all the 'numbers' one time and found that think thin had the highest protein, lowest sugar and calories, as compared to all the others. Peanut Butter is the best tasting.
Costs about 1.69 each. Can get them at Krogers, Trader Joes and Whole Foods.
I go back to them time after time, though I try not to eat often, whole food is better. But a good fill-in when I can't get whole food in die to schedule.
Another alternative is a small bag of unsalted, whole almonds with rasins in my purse at all times. Clean food, great protein and stabilizes hunger and blood sugar if my schedule is crazy... keeps me on track with 5 meals a day.