Dual use lighthack?

Not really sure if this would be considered dual use. I know that the lighthack is only usable on the windows 7 consoles but is it possible to add an ethernet shield and have it work with both XP and 7 based systems. The ideal scenario is plug into a windows 7 system with usb but when i come across an older xp system hook up the ethernet to get it working.

 

If it is possible my next question would be would i be able to use a crossover cable to connect direct to the console or do i need to use a router?