I made these this afternoon and the family loved them!

Scone Dough:
2 cups all-purpose flour
1/4 cup granulated white sugar
2 teaspoons baking powder
1/8 teaspoon salt
6 tablespoons chilled, unsalted butter, cut into pieces
1 cup fresh blueberries
1 large egg, lightly beaten
1 teaspoon pure vanilla extract
1/2 cup milk or cream
Brushing tops of scones:
Milk or Cream
Streusel Topping:
1/4 cup brown sugar
1/4 cup all purpose flour
1/2 teaspoon ground cinnamon
2 tablespoons chilled unsalted butter, cut into pieces

Preheat oven to 425 degrees F and place rack in middle of oven. Line a cookie sheet with parchment paper. 
For the Scones: In a large bowl  whisk together the flour, sugar, baking powder and salt. Cut the butter into small pieces and blend into the flour mixture with a pastry blender or two knives. The mixture should look like coarse crumbs. Gently fold in the blueberries. In a small measuring cup combine the cream, beaten egg and vanilla. Add this mixture to the flour mixture and stir just until the dough comes together. Do not over mix the dough or the scones will be tough.
Transfer the dough to a lightly floured surface and knead  the dough gently four or five times and then pat the dough into a circle that is about 7 inches  round and about 11/2 inches  thick. Cut this circle in half, then cut each half into four pie-shaped wedges (triangles).  Place the scones on the baking sheet. Brush the tops of the scones with a little cream or milk.
For the Streusel Topping: In a small bowl whisk together the sugar, flour, and cinnamon. With a pastry blender or two knives, cut in the butter until crumbly. Top each scone with a teaspoon or two of the streusel mixture. Cover and refrigerate any leftover streusel mixture.
Bake the scones until nicely browned, about 15 - 20 minutes or until a toothpick inserted in the center of a scone comes out clean. Transfer to a wire rack to cool slightly. These are best eaten the day they are made but can be covered and stored for a few days.
Makes 8 scones

From the Joy of Baking

Preparedness, when properly pursued, is a way of life, not a sudden, spectacular program. -- Spencer W. Kimball, 1976