I picked up x2 Toshiba 1TB 2.5 portable USB drives for my uncles server backups. They seem to work fine. I like their enclosures, small with rubber edge, feels solid.

They don't make em anymore but perhaps there is a newer model of them out.
http://www.newegg.com/Product/Product.aspx?Item=N82E16822149103

-Ben
HT v2.0
HT v1.0