This paper describes the XYZ, a new open-source sensing platform specifically designed to support our experimental research in mobile sensor networks. The XYZ node is designed around the OKI ML67Q500x ARM THUMB Microprocessor and the IEEE 802.15.4 compliant CC2420 radio from Chipcon. Its new features include support for two different CPU sleep modes and a long-term ultra low power sleep mode for the entire node. This allows the XYZ and its peripheral boards to transition into deep sleep for extended time intervals. To support mobility hardware control and computations, XYZ supports a wide dynamic range and power options. In low power configuration the node resembles existing small low power nodes. When needed, the node can scale up its resources to perform more powerful computations. Mobility is enabled with an additional accessory board that allows the node to move along a horizontal string. In this paper we provide an overview of the XYZ architecture and provide an insightful power characterization of the different operational modes to allow the users to optimize their platforms for power.