I enjoy finding quality wallpaper to place on my desktop every now-and-again to spice up my dull life and every month Smashing Magazine provides the nicest you can find. Like this one by Maryam Kazerooni from US / Iran.
The best part about these particular Desktop pics is they all have a monthly calendar right there for your viewing pleasure. No need to fumble through that drawer or click on that calendar button, simply look up and all your questions can be answered. (as long as they are calendar based)
(Check them all out HERE)