function launchWindow(id) 
{	
	//Get the screen height and width
	var maskHeight = $(document).height();
	var maskWidth = $(window).width();

	//Set heigth and width to mask to fill up the whole screen
	$('#mask').css({'width':maskWidth,'height':maskHeight});
	
	//transition effect		
	$('#mask').fadeIn(1000);	
	$('#mask').fadeTo("slow",0.8);	

	//Get the window height and width
	var winH = $(window).height();
	var winW = $(window).width();
          
	//Set the popup window to center	
	$(id).css('top',  winH/2-$(id).height()/2);
	$(id).css('left', winW/2-$(id).width()/2);

	//transition effect
	$(id).fadeIn(2000); 	 
}