JkDefrag is a free (released under the GNU General Public License) disk defragment and optimize utility. Completely automatic and very easy to use, fast, low overhead, with several optimization strategies, and can handle floppies and USB disks/sticks. Included are a Windows version, a commandline version (for scheduling by the task scheduler or for use from administrator scripts), a screensaver version, a DLL library (for use from programming languages).
What's new in this version:
This version is the first release on CNET Download.com.