<SCRIPT LANGUAGE="JavaScript">

 
// define variables
 
var month_names = new Array("Ene","Feb","Mar","Abr","May","Jun","Jul","Ago","Sep","Oct","Nov","Dic");
var days_in_month  = new Array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
var this_date = new Date();                                   // get todays date
var this_day = this_date.getDate();                           // returns date within month - range 1-31
var this_month = this_date.getMonth();                        // returns month within year - range 0-11

function makeCalendar(the_month, the_year)
{   first_of_month = new Date(the_year, the_month, 1);        // creates instance of date object for first of month
    day_of_week = first_of_month.getDay();                    // returns day within week - range 0-6
    if  (((the_year % 4 == 0) && (the_year % 100 != 0)) || (the_year % 400 == 0))
    {   days_in_month[1] = 29;                                // it's a leap year so change # days in Feb in array
    }
    else
    {   days_in_month[1] = 28;                                // not leap year - future use if multi year calendar built
    }
    document.write("<TABLE CALLSPACING=0 CELLPADDING=0>");    // start building the month table
    document.write("<TR BGCOLOR='maroon'><TH COLSPAN=7>" + month_names[the_month] + " " + the_year);        // month and year heading
    document.write("<TR BGCOLOR='orange'><TH>S</TH><TH>M</TH><TH>T</TH><TH>W</TH><TH>T</TH><TH>F</TH><TH>S</TH></TR>");    // day of week heading
    document.write("<TR ALIGN=RIGHT>");
    var column = 0;
    for (i=0; i<day_of_week; i++)                             // skip to day_of_week value for first_of_month
    {   document.write("<TD> </TD>");
        column++;
    }
    for (i=1; i<=days_in_month[the_month]; i++)
    {   if  ((i == this_day)  && (the_month == this_month) && (the_year == this_year))
        {   document.write("<TD BGCOLOR='red'><B>" + i + "</B></TD>");       // highlite todays date
        }
        else
        {   document.write("<TD BGCOLOR='black'><B>" + i + "</B></TD>");       // no highlite for other dates
        }
        column++;
        if  (column == 7)                                     // start next row of dates for month
        {   document.write("</TR><TR ALIGN=RIGHT>");
            column = 0;
        }
    }
    document.write("</TR></TABLE>");                          // month complete - close table
}
   
function y2K(number)                                          // if year < 2000 javascript gives only 2 digits for year
{ return (number < 1000) ? number + 1900 : number;
}
 
var this_year = y2K(this_date.getYear());
// -->
                       
</SCRIPT>

<SCRIPT LANGUAGE="JavaScript">

<!--
 
document.write("<TABLE BORDER='5' bgcolor=orange><TR VALIGN=TOP><TD>");
makeCalendar(0, this_year);                                   // we are passing the month and year to build the calendar
document.write("</TD><TD>");                                  // in JavaScipt the first month is 0
makeCalendar(1, this_year);
document.write("</TD><TD>");
makeCalendar(2, this_year);
document.write("</TD><TD>");
makeCalendar(3, this_year);
document.write("</TD></TR><TR VALIGN=TOP><TD>");
makeCalendar(4, this_year);
document.write("</TD><TD>");
makeCalendar(5, this_year);
document.write("</TD><TD>");
makeCalendar(6, this_year);
document.write("</TD><TD>");
makeCalendar(7, this_year);
document.write("</TD></TR><TR VALIGN=TOP><TD>");
makeCalendar(8, this_year);
document.write("</TD><TD>");
makeCalendar(9, this_year);
document.write("</TD><TD>");
makeCalendar(10, this_year);
document.write("</TD><TD>");
makeCalendar(11, this_year);
document.write("</TD></TR></TABLE>");
document.close();
 
// -->
                       
</SCRIPT>

holas!!!!!! disculpa me parece muy bien tu contador quiciera saber como haria yo para implantar en un sistema ese codigo pero que me contara el tiempo en q un usuario inicia una secion y que pare cuando el usuario cierra la sesion si me puedes ayudar lo agradeceria....

chao q estes bien.....

<script language="JavaScript">
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//Pictures to switch inbetween

var Rollpic1 = "img22.jpg";
var Rollpic2 = "img23.jpg";
var Rollpic3 = "img24.jpg";

//Start at the what pic:
var PicNumber=1;
//Number of pics:
var NumberOfPictures=3;
//Time between pics switching in secs
var HowLongBetweenPic=5;

//SwitchPic Function
function SwitchPic(counter){

 if(counter < HowLongBetweenPic){
 
  counter++;
  
  //DEBUG in the status bar at the bottom of the screen
  window.status="Cambia imagen cada 5 segundos : "+counter+" - Imagen nº: "+PicNumber+" ";
  
  //Display pic in what <IMG> tag roll is what I called the image
  document.roll.src = eval("Rollpic" + PicNumber);
  
  //function calls itself
  CallSwitchPic=window.setTimeout("SwitchPic("+counter+")",500);
  
  }
  
  else{
   //if its not the last picture goto the next picture
   if(PicNumber < NumberOfPictures){
    PicNumber++;
    SwitchPic(0);
   }
   //its the last picture go to the first one
   else{
    PicNumber=1;
    SwitchPic(0);
    }
 
  }

}
// Stop hiding from old browsers -->
</script>