My favorite is LifeLock because they not only give a $1,000,000's worth of protection if you become a victim of Identity Theft while enrolled in their services they will also give you a free 30 day trial. During the trial you will recieve copies of all of your credit reports for free and they will make it so that if a Federal Bond and Collection Service employee tries to apply for credit in your name they will not be successful.
You really have nothing to lose but Your Identity.