Supporters of the Robin Hood tax are calling on world leaders gathered in South Korea for the G20 summit to listen to their people rather than the banks. They argue that banks that were bailed out over the past two years are now back to business as usual but that a global Robin Hood tax would mean the world's banks pay to reduce the deficits they helped to cause, removing the need for austerity measures. But will world leaders heed these calls and is the Robin Hood tax a feasible idea?