The European Commission is taking Greece to court for failing to change a law that could ban people playing computer games at home.
The law, which aimed to target gambling machines, also includes a ban on installing the games in public and private places - including cyber cafes.
The European Commission says the ban is "disproportionate".
Despite promising to amend the law after a request from the Commission, Greece has yet to introduce any change.
The Commission said the law was disproportionate, as it applies not only slot machines and games of chance, "which might give rise to social concerns, but also games of an entirely different nature which are not... a source of particular disquiet with regard to public order or consumer protection".
Commission spokesman Jonathan Todd told reporters: "The law makes it theoretically illegal to play your Game Boy at home or 'Snake' on your mobile.
"Fortunately in practice the law is not applied to prevent playing computer games at home, but is applied to prevent the installation or repair of computer games at places like cyber cafes," he said.
"The law hinders free movement of goods and provision of services. So unfortunately we are obliged to take Greece to the Court of Justice."