Cube CountDown script takes advantage of CSS3's transform property to display 3D cubes that rotate to count down to any desired future date. It supports either a horizontal or vertical layout, with its interface scalable on different screen sizes.
CountdownTimer is a reverse count down jQuery plugin for displaying countdown as per your need.
You can set a future date for reverse count down till that date from today or set start date and end date for reverse count down or you can set time in hours, minutes and seconds for reverse countdown to zero.
A tutorial about how to make a simple countdown timer using jQuery.