What about an unused licence for Windows 8?
I bought a licence for Windows 8 at the cheapo rate. When I tried to install, it fell over at the final hurdle thanks to something from Acronis.
Given the reports of woes for W8, I never got round to installing it.
So, if I try again, do I have to install * and then get 8.1?
Bet they haven't thought of that one.