painfularious 

Something so bad, so awful, it's downright painful but you can't help but laugh at it in misery.

I was on the train and this girl was singing Smash Mouth's All Star on her iPod, and singing it badly... it was so painfularious but I couldn't stop laughing.

painfularious by mdhattar December 28, 2010

Painlarious 

When something happens that is hilariously painful for the person/persons involved.

When Rondo of the Boston Celtics got close-lined by the Miami Heat's Igaulskas dick in the Celtics-Heat game on February 13th, 2011 it was Painlarious.

Painlarious by fanofdirtybball March 1, 2011