Macmall.com has the Western Digital 320GB My Passport for Mac USB 2.0 portable hard drive (model no. WDMEA3200AN) available for the sale price of $69.99, making it $30 less than its list price of $99.99 and the lowest cost we have found for this particular hard drive by about $5. Shipping rates start at $3.99 and sales tax will apply for residents of California, Tennessee and Wisconsin.

For some additional memory we have a couple Seagate FreeAgent Go USB 2.0 portable external hard drives which happen to also be on sale. First up we have the 500GB Seagate FreeAgent hard drive at BuyDig.com priced at $104 with FREE shipping included, second we have the 640GB Seagate hard drive which is only a little more expensive priced at $129.99, and has FREE shipping included as well. Continuing up the ladder we have the Western Digital My Passport Essential 1TB portable external hard drive, which is currently on sale at Amazon.com for $185 as opposed to its list price of $249.99, with shipping rates starting at $8.

The WD My Passport 320GB portable hard drive is designed to store files, images, music, videos and important documents. It comes pre-formatted for Mac OS X 10.4 or higher operating systems and transfers data at up to 480Mbps sing its high-speed USB 2.0 connection. The storage device also includes shock resistance technology, and is backed by a three year warranty through the manufacturer. Dimensions: (W) 3.1” x (H) 0.6” x (D) 5”; weight 6.3oz.