$59 for the Hitachi 640GB USB external hard drive
TigerDirect.com has the Hitachi 640GB USB external hard drive (model no. H3640U) for $59.99, which is $10 off the original price of $69.99 and the lowest price we could find on this hard drive by about the same price margin. Shipping rates start at around $11 and vary by your location and method of delivery. Sales tax applies for residents of FL, IL, TX, and NC.
The 640GB Western Digital Elements hard drive is priced at $64.99 with $6.59 for shipping at Buy.com.
For about $80 more ($139.99 with $1.99 for shipping) is the 1.5TB Seagate FreeAgent external hard drive, also available at TigerDirect.com.