Parascroll.js provides a simple parallax image scroller that can be easily incorporated into any website. It is perfect for backgrounds on "hero"-style elements, but can be used on any element with a background.
To mark an element for the parallax effect, simply add the class "parallax-bg" and the attribute "data-bgurl," like so:
<div class="parallax-bg" data-bgurl="path/to/image.png">...</div>
Once you include the script at the bottom of your file, it will automatically set up parallax scrolling. Note that any elements added dynamically will not be affected.
Once I set up the Github Pages site for parascroll.js, I will link it here.