jQuery.fn.autoGrowInput = function(o) {

    o = jQuery.extend({
        maxWidth: 1000,
        minWidth: 0,
        comfortZone: 70
    }, o);

    this.filter('input:text').each(function(){

        var minWidth = o.minWidth || jQuery(this).width(),
            val = '',
            input = jQuery(this),
            check = function() {

                if (val === (val = input.val())) {return;}

                // Enter new content into testSubject
                var escaped = val.replace(/&/g, '&amp;').replace(/\s/g,' ').replace(/</g, '&lt;').replace(/>/g, '&gt;');

                
                var testerWidth = Math.floor(escaped.length*5),
                    newWidth = (testerWidth + o.comfortZone) >= minWidth ? testerWidth + o.comfortZone : minWidth,
                    currentWidth = input.width(),
                    isValidWidthChange = (newWidth < currentWidth && newWidth >= minWidth)
                                         || (newWidth > minWidth && newWidth < o.maxWidth);

                // Animate width
                if (isValidWidthChange) {
                    input.width(newWidth);
                }

            };

        jQuery(this).bind('keyup keydown blur update', check);
        jQuery(document).ready(function() {check()});
    });

    return this;

};