Invest in some kids cones - they are TINY only about 5 calories per cone. You can only fit about 1 -2 tbls of ice cream, which is about 1/4 of a normal serving. You can have two of these "cones" be completely satisfied and have had under 200 calories! Depending on your ice cream - under 100!
Joy Brand has kiddie cones, and Edy has a slow churned ice cream that is yummy and low cal. Try with forzen yogurt also.