A modular power supply that can be adapted to receive and charge practically any type or number of portable electronic devices includes a power converter that receives an AC wall voltage and converts the wall voltage to DC bus voltage. Each charging module has a pair of conductive rails and magnets positioned around the exterior of the module. The power converter has a connector that is physically and electrically coupled to a charging module through a pair of magnets and conductive rails such that the DC bus voltage is applied to the conductive rails of the module. Each charging module has a dock that physically couples to a portable electronic device and supplies a charging voltage produced from the DC bus voltage to the device. Additional charging modules can be physically and electrically coupled together by simply placing the modules adjacent one another through the interaction of the module's conductive rails and magnets. Adapters can be inserted into the docks of the charging modules to reconfigure the docks stations to mate with different types of devices. An FM transmitter can be included in one of the modules to transmit audio from the charging device to a remote FM receiver.