I would like to state my appreciation for static backgrounds. By having one constant background which doesn’t scroll with the content, the page is subtly differentiated from most websites which can make a big impression on viewers. Despite the positive, I think they could easily be overused with a distracting background.
An example of the CSS code to create a static background is:
background-image: radial-gradient(#FFFFFF,#2f285a);
background-repeat: no-repeat;
background-attachment: fixed;