If you get bored with displaying the same wallpapers fast, and feel inclined to try out something new, now and then, head over to the Windows 7 Personalization Gallery to download these two new Abstract themes from Microsoft.
Dramatic abstract designs suggestive of smoke, gears, feathers, and circuits are featured in this free theme for Windows 7.
You can if you wish, also preview the wallpapers before you download the theme?
This bold and unusual free theme for Windows 7 features fractals, sunbursts, floating spheres, and other designs evoking heightened spiritual states and unknown dimensions.
If you are a Windows 7 Starter and Home Basic Editions user then this Personalization Panel may help you implements the personalization features which are available in other editions.