Lemonade Cheesecake

8 ounces cream cheese
1 (14 ounce) can sweetened condensed milk
1 (6 ounce) can frozen lemonade concentrate, thawed
1 (12 ounce) container frozen whipped topping, thawed
2 graham cracker pie shells

Beat cream cheese, condensed milk and lemonade concentrate until smooth. Add whipped topping. Divide into two graham cracker shells. Serve as is or topped with more whipped topping. Freezes well (without topping). Thaw in refrigerator.