The Kursk Icon
of the Mother of God, also called the Kursk Root icon, is due to come to Russia and Ukraine, and possibly Kazakhstan, in visits to various churches during 2011.
From the 'Voice of Russia' article:
Legend has it that in the 14th century the Tatar-Mongol invaders cut the icon in two but when an Orthodox priest put the parts together they miraculously become one again.
Other information here: http://orthodoxwiki.org/Kursk_Root_icon