Suppose there is a faded image. But it becomes clear and original on mouse over, it is called tilt-shift effect. This kind of erffect looks nice in case of image gallery or any other kind of protfolio website. You can easily implement this with the help of CSS3 and jQuery.
But opensource world has everything so you do not need to code most of the things. For Tilt-shift effect, there is a nice jQuery plugin available called TiltShift.js. This nice plugin uses CSS3 image filters to replicate the tilt-shift effect. They only drawback of this plugin is that it only works for Chrome and Safari 6.
This plugin also comes with many customization options which includes defining focus point, blur radious, the amount of area that is in focus, the amount of area between complete focus and complete blur, and the direction of the effect.
Requirements: jQuery framework
License: GPL License