$.fn.stickyfloat = function(options, lockBottom) {
    var $obj                = this;
    var parentPaddingTop    = parseInt($obj.parent().css('padding-top'));
    var startOffset         = $obj.parent().offset().top;
    var opts                = $.extend({ startOffset: startOffset, offsetY: parentPaddingTop, duration: 200, lockBottom:true }, options);
    
    $obj.css({ position: 'absolute' });
    
    if(opts.lockBottom){
        var bottomPos = $obj.parent().height() - $obj.height() + parentPaddingTop;
        if( bottomPos < 0 )
            bottomPos = 0;
    }
    
    $(window).scroll(function () { 
        $obj.stop(); 

        var pastStartOffset         = $(document).scrollTop() > opts.startOffset;   
        var objFartherThanTopPos    = $obj.offset().top > startOffset;  
        var objBiggerThanWindow     = $obj.outerHeight() < $(window).height();  

        if( (pastStartOffset || objFartherThanTopPos) && objBiggerThanWindow ){ 
            var newpos = ($(document).scrollTop() -startOffset + opts.offsetY );
            if ( newpos > bottomPos )
                newpos = bottomPos;
            if ( $(document).scrollTop() < opts.startOffset ) 
                newpos = parentPaddingTop;

            $obj.animate({ top: newpos }, opts.duration );
        }
    });
};