$(document).ready(function(){
    var login_form_down = false;
    $('#login_button').click(function(){
        if(!login_form_down)
        {
            $('#login_form').animate({'top': '45'}, 250, 'swing', function(){
                login_form_down = true;
            });
        }
        else
        {
            $('#login_form').animate({'top': '-124'}, 250, 'swing', function(){
                login_form_down = false;
            });
        }
        return false;
    });
});