Western Digital RE WD2001FYYG 2TB 7200 RPM 32MB Cache SAS 6Gb/s 3.5" Enterprise Internal Hard Drive Bare Drive - £107.99 (29% off) - Newegg

[KevinP]

Wouldn't really recommend this for any standard user usage, but if you're looking to make a reliable NAS/storage server this may be good for you.

http://www.newegg.com/global/uk/Product/Product.aspx?Item=N82E16822236355&ignorebbr=1