UltraDefrag is powerful Open Source defragmentation tool for Windows NT.
It's engine is very fast, because it is created as kernel-mode driver.
They are three interfaces to them: graphical, console and native.
First is very useful, because it use cluster map visualization. Console is good
for task scheduler, and native tool - for advanced users and programmers.
- fix 'stop' function and some other significant bugs
Tools and Utilities
Product page: here