Commentators like to refer to Portugal, Italy, Ireland, and Greece collectively as the PIIG countries.

FORBES: The Real Problem With Obama's Tax-Cut Priorities

As Greece and Ireland flounder in Europe, many analysts are turning their gaze to Portugal, the PIIG nation deemed most likely to follow suit.

FORBES: Forget Portugal, Says Roubini -- Worry About Spain

When the debt crises flairs up in any of the PIIG countries, it usually weakens the Euro, bringing the stronger countries (a relative term) to the rescue.

FORBES: The Real Problem With Obama's Tax-Cut Priorities