Open Media Server - NAS and UPnP SD Card
8GB SDHC Memory Card with Raspbian, Samba and UPnP preloaded and configured to convert your Raspberry Pi into a NAS and UPnP server. The way this card has been setup is explained in the tutorial Raspberry Pi NAS and DLNA / UPnP. It comes with a SD adaptor, to make it easy to overwrite it in the future and use it for something else.
Just connect a NTSF formatted hard drive to one USB port of the Raspberry Pi (make sure only one hard drive is connected) and connect the Raspberry Pi to your router with an Etherner cable, power up the Raspberry Pi and it should be ready to go.
The tutorial Raspberry Pi NAS and DLNA / UPnP explains how to do the connections.