An electronic token system including a token receptacle and a portable token. The token receptacle includes a receptacle body with an outer surface having a first, generally planar array of electrical contacts, which are arranged in a dense-packed configuration that minimizes the surface area occupied by the planar array, consistent with sufficient electrical separation between adjacent contacts. The token receptacle also includes a first alignment feature and a first retention feature. The portable token includes an enclosure for enclosing at least a portion of the receptacle body, the enclosure having a second alignment feature for mating engagement with the first alignment feature and a second retention feature for holding the portable token in removable connection with the first retention feature. The token also includes a second, generally planar array of electrical contacts for electrical communication with the corresponding electrical contacts of the first planar array mounted in the token receptacle.