CSS: Background Images for Hi-Resolution Displays (like Apple's Retina)

I ran into a task today that led me to wonder about the best approach to create and implement CSS background images for hi-resolution displays like those found on more and more mobile phones and tablets. Hi-res displays, like those phone on the iPhone, iPad, Kindle HD, and the latest Motorola Droid and Samsung Galaxy phones, are capable of rendering stunning, sharp images—but only if you supply them through your Website or app. What I found in my research was this great, understable, and quick read by Lee Munroe on his Website. Read it there to learn about the best approaches to deliver hi-quality images to devices that will support them.