Since the opening of the Grantanamo prison, 38 of the 759 prisoners have been deemed "no longer enemy combatants." Right now there are four men at Guantanamo who have been cleared of all charges, but who have no idea when they will be released.
Many of the men who have been cleared of charges were rounded up by profiteers on the Pakistan/Afghanistan border and sold to U.S. or Northern Alliance forces, according to The Washington Post. The going prices were rumored to be $25,000 for each Arab, and $15,000 for each Afghan. Some were Arabs who "stood out," and some were arrested by the Pakistani police.