A power source for a vehicle includes at least one toroidal ring positioned in a housing. The toroidal ring includes magnetic material such as permanent magnets. The toroidal ring is magnetically levitated in the housing. A propulsion winding is coupled with the housing and energizable via a power signal to move the toroidal ring. Once moving, the magnetic material and the propulsion winding cooperate to produce electrical power and/or provide a stabilizing effect for the vehicle. In some applications, such as in an aircraft application, two or more toroidal rings may be used and rotated at counter directions so as to produce a predetermined net angular momentum.