GREEK STOCKS ARE PLUMMETING

That's because the European Central Bank (ECB) announced after European markets had closed that it would no longer accept Greek government bonds as collateral for lending.

It hasn't accepted them at any other banks in Europe for years, because they're junk-rated (not very safe), but Greece got an exception because it was in a bailout programme. That waiver has now been snatched away.

Greek banks are down by more than 20% already, after a roller-coaster ride in recent weeks. Greece's major banks lost almost 40% of their market value in the days immediately after the election, before making most of that back again at the end of last week, ahead of today's collapse.