zp_picturefill Nov 08, 2013 / Updated: May 05, 2014
A plugin to responsively provide different image resolutions for different screen sizes as well as standard and HiDPI ("Retina") counter parts.
An adaption of Picturefill by Scott Jehl - https://github.com/scottjehl/picturefill
Now for picturefill 2.x with the new <picture> element.
This extension is hosted and (hopefully maintnained) by its author.