Command Line
Yes, I'd second this. For system maintenance, it would be great to be able to add a command line to a batch file to regularly defrag databases, game files, etc for performance. Not just a drive, but drives, directories or files.
Interface
As well, here's another suggestion regarding the interface. For drive defragging (the current version 1.1.58 beta), the interface is split into 3 sections: the drive, the graph and the file listing. My suggestion is that when you choose "Defrag folder" under the Action menu, then the top section change from a drive list to a folder tree. That way, you're not opening a popup, and the user can see what they're doing in a consistent interface.
Or better yet, have the drive listing able to expand like a tree view to show folders and files, that way all three defrag options are all in the same consistent interface.
Usability
When I analyzed my C: drive, I sorted the list by path because I wanted to defrag a bunch of files in a few particular directories. So I checked off about 20 files, defragged them, but found that there was no way to "deselect all" so that I could scroll to the next set of files to defrag (instead I had to deselect each file one by one). A number of applications allow you to right-click in that area to produce a menu with things like "Select all", "deselect all", etc.
Windows Integration
Would be nice if we could have a contextual menu item added in Windows explorer to defrag selections!
good job so far!
cheers
Gantry