So far I have been using flash drives to store data from my RPi Torrent box. But the flash drives get filled up quickly, and one of my cheap flash drives stopped working after some time (Probably due to the large amount of writes issued when downloading torrents). I always wanted to have my files stored on a central location so they can be accessed by any machine on the network. So I hooked up a hard disk to the RPi. The RPi will not provide enough power for a normal external hard drive to operate, and therefore I used a SATA hard disk, and fixed it in to a hard disk enclosure which provides a SATA to USB interface, and provides the required power externally.