Richard Nakka has developed a rocket motor, which is said to be the cheapest rocket motor. The total cost of this experimental rocket motor is just two dollar. It has the ability to create thrust force to propel the rocket into the air making fire, smoke and noise.

Richard has used the household articles like hand screwdriver, power screwdriver, metal pot, pipe cutter and other common materials to design his armature rocket motor, which can launch a rocket in a suitable location like other motor.
He used several inches of slow-burning canon fuse, copper end cap, 1/2 inch copper pipe for the motor casting. For fueling, he took table sugar, heavy corn syrup, salt-peter and a glass of water. All these materials will not cost more than two dollars. The amateur rocket motor is in the testing stage. It can last for at least three firings.
Via: Instructables