School starts for me on Monday, and I need a computer, so I installed WinXP with the following technique:
1) take the HD out and put it in a computer with a cdrom drive
2) install DOS on the HD using cdrom (can't use WinXP)
3) copy XP install cdrom directory into a directory that DOS can see, optionally copy SMARTDRV.EXE to root of DOS FS (to speed up WinXP install).
4) put the HD back into the target machine
5) if you had used WinXP here, you wouldn't be able to boot, but DOS is sufficiently hardware agnostic that you can get a command line
6) optionally run SMARTDRV.EXE, and then run WINNT.EXE, which is located in the I386 subdirectory of the install CD folder.
7) end with XP on a FAT parition; optionally use partition magic or like program to change partition to NTFS
I recommend that if anyone wants to try this, they buy a $10 IDE to USB adapter to greatly simplify things. Also, the paritioning scheme for the target HD should have a 5+ GB FAT partition as the first partition; this is where you'll install DOS.
The UDA represents a significantly quicker and more robust solution to diskless installs, so if you have time, I'd still like to get it working.