Bring water to a boil. Add butter and salt. Add flour & remove from heat. Beat with a fork until well-mixed. Beat in the eggs and cinnamon. Put the mixture into a pastry bag. Heat about an inch of oil in a pan, or use a deep fryer, to about 350F. Squeeze the mixture into the oil, making the churros about 7" long. Cook 3-5 at a time, depending on how large your skillet or pan is until they are a nice golden color, turning occasionally. Drain on paper towels. Transfer to another dish, sprinkle sifted powdered sugar over them, and serve immediately. Makes about 18