This morning, ADE @ Microsoft Croatia Marko Sever informed me of the latest release on Japanese MSDN which includes Windows Phone Apps Art that you can use in your applications. They offer a variety of image material that can be used to express richer applications.
So, the gallery includes more than 600 useful figures, graphics and pictures only to use in Windows Phone applications. If you wish to use the images, you need to accept the Terms and Conditions of Use. One part of the license says that
…A user may freely download, duplicate, modify, cut, enlarge, reduce, deform, change the color, and rotate the Materials in order to produce Windows Phone applications. Applications that are produced using the Materials may be disclosed or distributed free of charge or for value, but such applications must be Windows Phone applications…
I downloaded a few of those and I must say that they look interesting and useful. Free artwork and images for Windows Phone developers! What are you waiting for? To start using it, go to: http://msdn.microsoft.com/ja-jp/windowsphone/hh544699