I made this up today and thought I would share. It's what I think is the perfect balance of lemon and raspberry, sweet and tart.
2 cups fresh squeezed lemon juice
8 cups water
1 1/4 cups sugar
1 basket of fresh raspberries
2 cups of ice
mix the lemon juice and 6 cups of water in a one gallon pitcher, put remaining 2 cups of water and the sugar in the blender and blend until the sugar is dissolved then add the raspberries and puree until smooth, add to pitcher add ice and stir well.