Stolpersteine (Stumbling Stones) by Guenther Demnig - An artist decided to commemorate Jews killed in the Holocaust. He placed these plaques in front of the homes where the victims used to live. There are now tens of thousands across cities throughout Europe. "Demnig says formal memorials are too abstract. Not so with the stumbling stones. 'Suddenly they are there, right outside your front door, at your feet, in front of you,' he says."