ive embodiment of button-shaped magnetic elements that can be used to create the magnetic force systems shown in FIGS. 18A, 18B, 18C, 19A, 19B, and 20. [0053]FIG. 22 is a side section view of a button-shaped magnetic element taken generally along line 22-22 is FIG. 21. [0054]FIGS. 23A and 23B are a representative embodiment of a button-shaped magnetic element that can be used to create the magneti