Article:
http://ivopetkov.com/b/lazy-load-responsive-images/
In this demo, you'll find four div tags with various sizes. When the image inside each div becomes visible on the
screen, the best version is selected and loaded. The available versions widths are 400px, 600px, 800px, 1000px, 1500px,
2000px, 2500px. You can easily see which version is loaded via the text inside the image.
