Machine Crunch:

Lay down on a crunch machine. Read all the instructions on the machine, and perform the workout according to the instructions.  Instructions are generally as follows: Grab the upper handles with your hands. Inhale. Contract your abs to bring your head towards your feet, although this is a small movement, so you only go a few inches. Squeeze your abs hard in the top position.
Slowly lower back to the starting position and repeat for reps.