So you said any ideas, right? I first idea was to ask you if you'd like to have another Pentium III and I will donate it to you.
But that may be not what to want to hear. You want to install an operating system without any way to boot from the BIOS. Yes, there is a way to do that. It is buried in the Microsoft knowledge base somewhere in the stuff about installing Windows in the when you don't have a way to install from the CD drive. I have used it just one time to install windows XP, or Dell machine that would barely meets requirements. I got it to work, it is not something I would ever want to do again.
Also, I don't think I would want to tell you how to do it. Not unless you insult me real bad and I come to hate you real bad and then I'll show you how to do it.Because this is the sort of thing you would want to inflict only upon your enemies, and not upon your friends.
The problem is that MS-DOS does not have a built-in memory management unless you look at boot time. Something like the HIMEM.SYS something like that. Otherwise, it takes ages to install windows XP street from MS-DOS.