You can register any email address as a Microsoft account.

>So I'm finally starting to play around with windows 8.1 and noticed something that kinda bothers me. If I want to use things like Skype or OneDrive (and some other things) from the tile menu, it asks me to log into my tablet with my Microsoft Account. But doing so means now I'm logged into my PC with my MS account, not the account I setup for myself. That really REALLY stinks! For Skype it's easy enough work-around -I just run the desktop version of Skype and not the windows 8.1 version. But I want to use the windows 8.1 version. Is there a way around this? If not then Microsoft has ticked me off (again).