I'm in love with Cortana, can't wait to actually use and and hopefully Microsoft will make it available for Windows 8.1 (PC/tablet) as well and not only on Windows Phone 8.1. Anyway, I decided to make this "wallpaper" if you can at least call it that way that brings that sexy logo on your desktop
I'm also thinking about making a sound pack for Windows. For example, when you login, to actually hear Cortana say "Hi. I'm Cortana."
I made the wallpaper using a 1920x1200 resolution.