The miricle-working Kursk icon of the Mother of God was kept on big feastdays on the mantlepeice of the ROCOR synodal headquarters dining room (I mean after services). Once a woman was walking by, and the icon fell on her head. It hit so hard that the woman was taken to the hospital for XRays.
The icon itself had done no damage, but they discovered a large tumor growing in her brain. It was just in time for treatment.