Western Digital 750GB My Book Essential USB External Hard Drive $99.99 shipped at Dell Home
Next lowest price on PriceGrabber is $119.99.

Dell Home has the Western Digital My Passport Essential 250GB USB 2.0 Portable Hard Drive for $80 after $26 Coupon discount + $5 shipping
Apply Coupon Code 47RSGPRJBHT1LL at check-out for $26 off (ends 10/15 or after 1500 uses)
Pay with Dell Preferred Account and receive an additional 3% discount - select “Credit Card” as payment option to see the deal
The Western Digital My Passport Essential 250GB USB 2.0 Portable Hard Drive features Data transfer rates up to 480 Mbps, 5400 rpm, and 12 ms average read seek time
Dell Home has the Western Digital 750GB External Hard Drive for $100 after $50 Coupon discount w/ free shipping
Apply Coupon Code 1Z5JB0QWTPVK9Z at check-out for $50 off (ends 10/15 or after 1500 uses)
Pay with Dell Preferred Account and receive an additional 3% discount - select “Credit Card” as payment option to see the deal
The Western Digital 750GB External Hard Drive features 16 MB buffer, 480 Mbps data transfer rate, and USB 2.0 interface
1SaleaDay.com has the Cavalry 1TB SATA 16MB Cache Internal Hard Drive for $110 + $6 shipping = $116 shipped. Includes Full Feature Backup Software. The drive is a Western Digital WD10EACS with 3-year warranty. [BizRate]