Turns a given div element into a dynamic clock that updates every second, main advantage compared to other similar plugins is that this one can also take an initial timestamp instead of client system time.
Try the demo at http://jsbin.com/ugapo3/8.
Unfortunately jsbin doesn't allow for server-side coding so it doesn't show the server timestamp example.

USAGE:

Use defaults:

$("div#clock").clock();


By default prints the date together with the time, but can be used for time only:

$("div#clock").clock({"calendar":"false"});


Includes 6 language translations for days of the week and months of the year: English, French, Spanish, Italian, German, Russian. 

$("div#clock").clock({"langSet":"de"});


The language translations can be easily extended. To add portughese language:

$.clock.locale.pt = {"weekdays":["Domingo","Segunda-feira", "Terça-feira","Quarta-feira","Quinta-feira","Sexta-feira", "Sábado"],"months":["Janeiro","Fevereiro","Março","Abril", "Maio","Junho","Julho","Agosto","Setembro","October","Novembro", "Dezembro"] };

Then you can pass in your custom language set:

$("div#clock").clock({"langSet":"pt"});



Can take a custom timestamp:

customtimestamp = new Date();
customtimestamp = customtimestamp.getTime();
customtimestamp = customtimestamp+1123200000+10800000+14000; // sets the time 13 days, 3 hours and 14 seconds ahead
$("#clock").clock({"timestamp":customtimestamp});


This functionality can be useful to use server timestamp instead of client timestamp. Say you use php to set the value of a hidden input field to the server timestamp:

<?php
echo "<input id='servertime' type='hidden' val='".time()."' />";
?>

You can then start your clock using that timestamp (you must turn the string into a number with parseFloat, then multiply by 1000 for milliseconds):

servertime = parseFloat( $("input#servertime").val() ) * 1000;
$("#clock").clock({"timestamp":servertime});

It would be interesting to call an ntp timeserver and start clock with ntp's timestamp, in order to have precise time. I have never succeeded in calling an ntp timeserver myself...

Includes a handler to stop the clock, just pass "destroy".

$("div#clock").clock("destroy");