You could most likely get access to the ports (I know there are tools available) but I don't feel that brave at the moment
Imagine how many xbox HD's I could mess up if a buggy version was released. If I had a spare development computer I could work a bit more in this direction, but I think it would be more usefull to pursue the other option. Modifiying the kernel to do the locking/unlocking at boottime. I have some ideas - but not the time. I have some big projects at work I must finish.
Launching the program from floppy we haven't really gained much, since we can allready boot a DOS floppy with unlockx. I'm pretty satisfied with having this boot-option directly on the CD as explained above.
But someday I will look closer at the ATA command posibilities in the linux kernel. Newer kernel have an experimental PCI hotplug option. Maybe this can be used to detect/unlock an xbox drive.