This Hard Drive

Buy.com has the Western Digital Elements WDE1U5000N 7200rpm 500GB USB2.0 External Hard Drive With 8MB Buffer Cache for only $79.99 with free shipping.

Product description from Buy.com:

Plain, simple, reliable add-on storage. This external USB 2.0 drive is preformatted for immediate use. Simply plug it in to a USB port and you?ve got instant storage your PC or Macintosh.

High-speed USB 2.0 - For maximum perform!
ance; backward compatible with USB 1.1 ports

Plug and Play Storage - Just plug it in, connect the cable to add high-speed storage for both desktop and notebook computers

Rugged Metal Case - Compact, durable metal case for extra data protection

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Shop4Tech.com has the Eagle EB-240-00066 2.5″ SATA to USB2.0 mesh External Enclosure for $10 - 10% code SB10 (Expires 9/9) + $0 shipping = $9 shipped. Just add a SATA notebook drive to create your own external drive.
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Staples.com has the I/O Magic IUSB22HD 4200 RPM 2.2GB USB 2.0 Portable External Hard Drive for only $19.90.
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Newegg.com has the Seagate ST901203FGA1E1RK FreeAgent Go 5400 RPM 120GB USB2.0 External Hard Drive for $79.99 - $10 off coupon code “EMCADBBEE” (Expires 03/17/2008) = $69.99 with free shipping.

Product description from Newegg.com:

The Seagate FreeAgent Go data mover drive offers 120 GB of storage in a package smaller than a hardback novel! It’s ideal for professionals whose jobs require that they work on a variety of different computers. Take your own desktop environment with you, including web browser favorites, passwords, IM client and contacts, email client, cookies, settings and files, and save all your data directly to the FreeAgent, not on the computer you’re using: you’ll leave no trace of your session on the !
computer. The 5400 rpm FreeAgent Go connects via USB 2.0, and is compatible with PC computers running Windows Vista, Windows 2000 Professional, XP Professional or XP Home Edition; Macs with G3, G4, or G5 processors, running OS X 10.3.9 or higher; and Macs with Intel Core Duo or Core Solo processors, running OS X 10.4.6 or higher. For added security, the FreeAgent features 256-bit encryption for your sensitive files. You get the ease and security of working on your own computer, even when you aren’t!

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EagleBit.com has the Eagle EB-240-00066 2.5″ PATA to USB2.0 mesh External Enclosure for $0 + $5 shipping = $5 shipped. Just add a PATA notebook drive to create your own external drive.
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EagleBit.com has the Eagle Consus W-Series ET-CSWNASU2-BK 3.5″ IDE to USB2.0 & 10/100 Ethernet Aluminum External Enclosure for $45 - $10 off coupon code “D10WNASFEB” = $35 with free shipping. Supports hard drives up to 1TB size. Free EagleBit M-Series 2.5inch PATA to USB hard drive enclosure with purchase.
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Buy.com has the CMS Products ABSplus V2ABS250 5400rpm 250GB Sata To USB2.0 External Hard Drive $132.99 Shipped after $10 off $200 new customer coupon and $75 Exclusive Mail-In rebate (Expires 04/30/2008).
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ComputerGeeks.com has the A-Power 3.5″ USB2.0 Ext IDE HD Enclosure for $20 - $20 rebate (Expires 1/23) + $7 shipping = $7 shipped after rebate. It is constructed with Aluminum and Plastic components, and it is stackable if you have multiple units.
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EagleBit.com has the Eagle EB-240-00065 2.5″ PATA to USB2.0 mesh External Enclosure for $5 + shipping. Free shipping on $20 orders.
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EagleBit.com has the Eagle Consus W-Series ET-CSWNASU2-BK 3.5″ IDE to USB2.0 & 10/100 Ethernet Aluminum External Enclosure for $50 with free shipping. Supports hard drives up to 1TB size. Free EagleBit M-Series 2.5inch PATA to USB hard drive enclosure with purchase.
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