1. A method of storing data, comprising the steps of: (a) providing a memory that includes at least one cell and that is operative to program each said cell to represent any one of 2 N different patterns of N>1 bits as a respective one of 2 N ordered states of said each cell; (b) defining a transformation that maps each said pattern of N bits into a corresponding transformed pattern of N bits, with said pattern of N bits that is programmed by said memory as a lowest one of said states being mapped into a different one of said patterns of N bits; and (c) whenever receiving N data bits to store in one of said at least one cell: (i) mapping said N data bits to one of said transformed patterns of N bits according to said transformation, and (ii) programming said one cell to said state that represents said one transformed pattern of N bits.