Enables retina display graphics (@2x) to any jQuery powered website. Pings out into the images directory and sees if there's an @2x asset. If it exists, it swaps out the original for the hi-rez version. If not, it moves on to the next image.
Usage:
$(document).retina();
Requires @2x image, and height and width of the image to be constrained either by the original img tag or the surrounding div.
More info here: mrballistic.com/retina