Milt - Henri Marie Coanda was a Rumanian engineer/ scientist/ aircraft designer born in 1886 and he designed what could be considered the first turbofan/bypass engine in 1910, exploiting an effect he had observed where engine exhaust gases from a piston engined aircraft tended to follow the curved shape of the fuselage much further than expected.
He took the propeller off the piston engine and used the drive to power a compressor that forced air into a ring shaped combustion chamber and produced sufficient thrust to get the aircraft airborne (albeit briefly).
As ascend charlie has said, we see coanda effect on tail-booms as the downwash creates lift on one side of it (the angle the air hits the boom forces it around one side faster than the other).
The effect can be enhanced by blowing air through a slot along the length of the tail boom (NOTAR does this) which encourages and enhances the boundary layer.
The Sea King had a long strake added on the port side of the tail boom to break up this powerful lift because, with a wind from the right, the aircraft was trying to yaw right and full left pedal was frequently insufficient to prevent it.
I have seen pictures of a rotor system built in the 60s with circular section blades that had a blown slot long the top surface - it apparently worked but the engineering problems (weight and power required) associated with getting high pressure air up the rotor mast and along the blades meant it didn't see full production.