Millions of UK PlayStation users have been victims of "excessive and unfair" download charges, a tribunal has heard. A £2bn ($2.7bn) class-action brought against Sony by consumer campaigner Alex Neill claims the console maker prevented players from purchasing digital products outside of its own "closed eco-system". Anyone who bought a digital PlayStation game or an in-game download over a period of about 10 years to February this year could be eligible for compensation if the case succeeds. Defending its business model, Sony told London's Competition Appeal Tribunal that third-party stores posed a security risk and it also used software sales to subsidise sales of its consoles. Opening the case for the claimants, Robert Palmer KC said Sony had "implemented a sustained strategy" to exclude competition over digital distribution of products "by monopolising their sale through the PlayStation store".…