Working in 2 batches, place 1 quart ice cubes in a blender. add 1/2 can limeade, 6 ounces tequila and 2 tablespoons cointreau.
Blend at highest speed until drink is almost smooth. Pour into a pitcher and repeat with remaining ingredients. Store in the freezer.
To salt the Margarita glasses, pour a single layer of salt onto a salad plate. Moisten each glass rim with lime; dip each rim in the salt. Pour Margaritas into each glass; garnish with lime.
Serve immediately.
Yield: 8 6-ounce drinks.