My friend and I blend ice, espresso, and non-fat milk powder with a little Splenda. (It’s to taste, but I generally use the same measurement of ice and espresso, with a tablespoon or two of the milk powder.) Make sure you use espresso (or really really strong coffee) so that the coffee flavor is not diluted by the ice. Torani also makes sugar-free coffee syrups that can be added to punch up the flavor. We buy our Torani from Cost Plus World Market, because they have the greatest choice of sugar-free flavors.