The chaps over at Bigbruin.com take a look at the typical performance characteristics of the Western Digital Caviar Green 2TB hard drive, but since it is touted as being eco-friendly, they focus on the heat generation and power consumption, too. Here's a bit:

Newegg.com is presently out of stock on the Western Digital Caviar Green 2TB hard drive, but the price is listed as $299.99. While you might expect to pay a premium because it is a new product and presently the only 2TB drive available, the price does seem high. For comparison purposes, consider the Caviar Green drive with a 1TB capacity and 32MB cache memory. It currently sells for $99.99, so you could get 3TB of storage for the same price. While you wouldn't be as green by running three drives instead of one, you could create a RAID 5 array for improved performance and fault tolerance, while still having 2TB of storage space.

First, it has high geek appeal for being the first drive available with 2TB of storage space. Whether you need all that storage, or just want to brag that you have it, 2TB is a lot of space (but also a lot of data that could be lost with one drive failure).

Second, it lives up to the billing as a more eco-friendly type of drive. It runs cool, quiet, and used far less electricity than other drives tested. Using a Caviar Green drive would be a good idea for many applications, but especially in a NAS device or HTPC where noise, heat, and power consumption might be of particular interest.

Finally, while the expectation was that this drive would have reduced performance due to its green features, this was not an issue during testing. You will achieve higher performance with other drives out there, but the Caviar Green 2TB hard drive can hold its own in testign and real world use.