Tengo una cuenta regresiva en JQuery, aquí está el código:
Código HTML:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js" type="text/javascript" charset="utf-8"></script> <script src="js/jquery.countdown.js" type="text/javascript" charset="utf-8"></script> <script type="text/javascript"> $(function(){ $('#counter').countdown({ image: 'img/digits.png', startTime: '00:00:03:10', timerEnd: function(){ $("#container").fadeOut("slow"); } }); }); </script>
Código HTML:
jQuery.fn.countdown = function(userOptions)
{
// Default options
var options = {
stepTime: 60,
// startTime and format MUST follow the same format.
// also you cannot specify a format unordered (e.g. hh:ss:mm is wrong)
format: "dd:hh:mm:ss",
startTime: "00:00:03:10",
digitImages: 6,
digitWidth: 53,
digitHeight: 77,
timerEnd: function(){},
image: "digits.png"
};
var digits = [], interval;
// Draw digits in given container
var createDigits = function(where)
{
var c = 0;
// Iterate each startTime digit, if it is not a digit
// we'll asume that it's a separator
for (var i = 0; i < options.startTime.length; i++)
{
if (parseInt(options.startTime[i]) >= 0)
{
elem = $('<div id="cnt_' + i + '" class="cntDigit" />').css({
height: options.digitHeight * options.digitImages * 10,
float: 'left', background: 'url(\'' + options.image + '\')',
width: options.digitWidth});
digits.push(elem);
margin(c, -((parseInt(options.startTime[i]) * options.digitHeight *
options.digitImages)));
digits[c].__max = 9;
// Add max digits, for example, first digit of minutes (mm) has
// a max of 5. Conditional max is used when the left digit has reach
// the max. For example second "hours" digit has a conditional max of 4
switch (options.format[i]) {
case 'h':
digits[c].__max = (c % 2 == 0) ? 2: 9;
if (c % 2 == 0)
digits[c].__condmax = 4;
break;
case 'd':
digits[c].__max = 9;
break;
case 'm':
case 's':
digits[c].__max = (c % 2 == 0) ? 5: 9;
}
++c;
}
else
elem = $('<div class="cntSeparator"/>').css({float: 'left'})
.text(options.startTime[i]);
where.append(elem)
}
};
// Set or get element margin
var margin = function(elem, val)
{
if (val !== undefined)
return digits[elem].css({'marginTop': val + 'px'});
return parseInt(digits[elem].css('marginTop').replace('px', ''));
};
// Makes the movement. This is done by "digitImages" steps.
var moveStep = function(elem)
{
digits[elem]._digitInitial = -(digits[elem].__max * options.digitHeight * options.digitImages);
return function _move() {
mtop = margin(elem) + options.digitHeight;
if (mtop == options.digitHeight) {
margin(elem, digits[elem]._digitInitial);
if (elem > 0) moveStep(elem - 1)();
else
{
clearInterval(interval);
for (var i=0; i < digits.length; i++) margin(i, 0);
options.timerEnd();
return;
}
if ((elem > 0) && (digits[elem].__condmax !== undefined) &&
(digits[elem - 1]._digitInitial == margin(elem - 1)))
margin(elem, -(digits[elem].__condmax * options.digitHeight * options.digitImages));
return;
}
margin(elem, mtop);
if (margin(elem) / options.digitHeight % options.digitImages != 0)
setTimeout(_move, options.stepTime);
if (mtop == 0) digits[elem].__ismax = true;
}
};
$.extend(options, userOptions);
this.css({height: options.digitHeight, overflow: 'hidden'});
createDigits(this);
interval = setInterval(moveStep(digits.length - 1), 1000);
};
Espero puedan ayudarme.
Muchas gracias!
Respuesta: Cuenta regresiva con hora del server 
