what jQuery library does this?

I want to be a开发者_StackOverflowble to have the following UI. When you click on the close button on top, the row below it moves to the top and so on.

Is there a library for this?

You don't need a library for this. Just bind the click event of the close button to hide the row that it is contained in.

No library, just around four lines of jQuery:

$('.item').append('<div class="close">x</div>');

$('.close').live('click', function() {
    $(this).parent().slideUp();
});

And a demo: http://jsfiddle.net/Blender/pEVTv/8/