"on a similar thought to wanting to play a DVD on a wind-up phonograph!."
haha... well thanks for the laugh, but seriously
what a customer requested was that they have some custom hardware that is connected via parallel port to a pc. The pc is booted into dos and an application is run on immediate startup that sends a signal over the parallel port (this needs to be done in like less than 15 seconds - otherwise it could boot windows or linux and run )... As newer system (particuarly servers) are coming in we are finding that there is no parallel port, so I was looking into the difficulty of using a USB-to-Parallel connector and hacking dos a little bit to get some limited USB access....
Also, this is also legacy software that is not going to be fun to port over to another o/s because it has all kinds of dos specific code (although it is going to have to be at some time).... I realize that DOS does not support USB but I had heard that there were some people working on DOS USB Stacks that would allow limited USB device access...