The use of mobile handheld devices within the workplace is expanding rapidly. These devices are no longer viewed as coveted gadgets for early technology adopters, but have instead become indispensable tools that offer competitive business advantages for the mobile workforce. While these devices provide productivity benefits, they also pose new risks to an organization's security by the information they contain or can access remotely. Enabling adequate user authentication is the first line of defense against unauthorized use of an unattended, lost, or stolen handheld device. Smart cards have long been the choice of authentication mechanism for many organizations; however, few handheld devices easily support readers for standard-size smart cards. This report describes two novel types of smart cards that use standard interfaces supported by handheld devices, avoiding use of the more cumbersome standard-size smart card readers. These solutions are aimed at helping organization apply smart cards for authentication and other security services. Details of the design and implementation are provided.