The Raspberry Pi is a credit-card sized computer.
With the addition of this RFM12Pi expansion board to receive data via wireless from other OpenEnergyMonitor modules e.g emonTx or emonTH. A Raspberry Pi running an emoncms server can be used as a powerful emonBase base-station to log, process and visualise energy, temperature and other environmental data.
Data can be logged locally to the Raspberry Pi's SD card / external hard drive and/or to a remote emoncms server. Emoncms graphs and dashboards can be served from the Raspberry Pi's local web-server.
Raspberry Pi Foundation: www.raspberrypi.org
OpenEnergyMonitor Getting Started Guide: http://openenergymonitor.org/emon/guide