Not for us, but an interesting take on card design.
"The Large Iris card is the size of a typical greeting card 5" x 7". It functions as a mechanical iris similar to those used in photography aperture mechanisms. A tab on the card can be manually rotated to progressively open the hole in the center of the card up to a maximum size of two inches. The card also has slots on the reverse side which can hold a 2" x 3" photo that will be partially revealed when the iris is opened. See the video below for a demonstration of the card."
Source: Cardnetics
Source: Cardnetics