When working with recycled stock, one of the most time consuming tasks is removing all of the protruding nails from the stock. Most woodworkers would probably use a hammer or a pry bar to remove the nails.
However, I prefer a much quicker method. I like to use a pair of Vise-Grip style locking pliers, with the jaws set to a width where they just lock down onto the nail. Place the pliers onto the end of the nail perpendicular with the stock, and roll the pliers over onto the rounded back edge of the pliers. The rounded edge will help to prevent denting the stock, and the nail should easily slide out of the stock. To ensure that you will not dent the stock, place a thin piece of scrap wood under the pliers as you twist.
TIP: To avoid having the square jaws mark the stock, I prefer to begin with the jaws about 1/8" above the wood before locking onto the nail.