The high pin press is often used as a second exercise for low reps (3-5). Bill Crawford and the Metal Militia crew love this exercise and their success certainly warrants everyone to at least try it.
To do a high pin press, simply set the bar on the pins of your power rack or bench rack. Generally, the range of motion is about 3-5". It is highly advisable that you have a rack that allows small increments, similar to the bench racks and power racks that EFS sells.
Most people like to take a competition grip or slightly narrower when doing these. You want your elbows to be flared out at the top. I like to hold each rep for at least two seconds. Too many times I've seen people do these and they fail to hold at the top.
You should have rep records for several different hole spacings.