Fixed Center jQuery plugin « David’s Web Development Blog
Fixed Center is a jQuery plugin that allows you to position an element directly in the center of the screen. The element will always stay centered even when you resize the browser window or scroll horizontally or vertically. I created this plugin because the ones I found were either not browser compatible (they failed in IE) or they automatically set the display property of the element you wanted to center so that the element would always show, thus making it hard to apply animated hide/show animation effects.