Paul Thurrott takes a look at Windows Vista's Automatic Disk Defragmenter

Years ago, I wrote a review comparing various disk defragmenters. To my surprise, the Disk Defragmenter in Windows performed as well, or even a bit better than, the retail defragmenters that were then available. (Further complicating matters, Disk Defragmenter was made by Executive Software, now called Diskeeper, which of course sells its own disk defragmenter product.)

Windows Vista Feature Focus: Automatic Disk Defragmenter