Today I used a piece of equipment at the gym I'd never used before.
The smith machine is an amazing aid to lifting. Because of the additional rail-guide system, fewer stabilizing muscles are required to perform the movement. Today I used it for shoulder presses and felt like my risk of injury was far less than it is when using dumbbells. I normally find free weights better than machine exercises. That said, you can put together some great workouts using the smith machine. I wish I had discovered it earlier!