If you have a Nexus phone and are yet to buy a case for it then Google have got you sorted. They recently released 'Live Cases' and the service is actually pretty cool. Upload your photo, position and edit it as much as you like and get it delivered to you.
If you don't have a photo you want to use then they also have a pretty neat feature called 'Places Live Case' that lets you take a map from Google Maps and customize it to use on a case. They actually look a lot better than they sound. Check out Google's Live Cases here.