Smooth expansion of DIV with jQuery

var bigWidth=800;
$("#map").width() == bigWidth ?
 $("#map").fadeOut(300).fadeIn(300).fadeOut(300).fadeIn(300).animate({ height: 400, width: 400 }) :
 $("#map").fadeOut(300).fadeIn(300).fadeOut(300).fadeIn(300).animate({ height: 400, width: 800 });

Button click animation

$("button").click(function(){
 this.animate({ opacity: '0.1'}, "slow" );
 this.animate({ opacity: '1.0'}, "fast");
});