Responsive version of shortcode columns for WordPress. Haven't tested in ages, based on http://scottnix.com/wordpress-columns-shortcode/

gistfile1.txt

function snix_clean_shortcodes($content) {
    $array = array (
		'<p>[' => '[',
		']</p>' => ']',
		']<br />' => ']'
	);

	$content = strtr($content, $array);
	return $content;
}
add_filter('the_content', 'snix_clean_shortcodes');

function snix_responsive_boxes( $atts, $content = null ) {
    extract(shortcode_atts(array(
	'size'=> 'full-width', // full width box is default
    'type'	=> '',

    ), $atts));

	$size = ($size) ? ''.$size : '';
	$type = ($type) ? ' '.$type : '';

	if (strpos($size, "last") === false) {
	return '<div class="' .$size.$type. ' responsive-box">' .do_shortcode($content). '</div>';
	}
	else {
	return '<div class="' .$size.$type. ' responsive-box">' .do_shortcode($content). '</div><span class="cf"></span>';
	}
}
add_shortcode('rbox', 'snix_responsive_boxes');



/* css */

/* responsive-box full width */

.responsive-box { width: 100%; clear: both;}
.responsive-box img { float: left; width: 35%; margin-right: 4%; }
.responsive-box p img { margin-bottom: 0; }


@media (min-width: 700px) {

    /*
		responsive box sizing - size=""
		default is full width 100%
	----------------------------------------------------*/
	.one_half, .one_half_last { width:48%; }
	.one_third, .one_third_last { width:30.66%; }
	.two_third, .two_third_last { width:65.33%; }
	.one_fourth, .one_fourth_last { width:22%; }
	.three_fourth, .three_fourth_last { width:74%; }
	.one_fifth, .one_fifth_last { width:16.8%; }
	.two_fifth, .two_fifth_last { width:37.6%; }
	.three_fifth, .three_fifth_last { width:58.4%; }
	.four_fifth, .four_fifth_last { width:67.2%; }
	.one_sixth, .one_sixth_last { width:13.33%; }
	.five_sixth, .five_sixth_last { width:82.67%; }
	.one_half, .one_third, .two_third, .three_fourth, .one_fourth, .one_fifth, .two_fifth, .three_fifth, .four_fifth, .one_sixth, .five_sixth { float: left; margin-right: 4%; }
	.one_half_last, .one_third_last, .two_third_last, .three_fourth_last, .one_fourth_last, .one_fifth_last, .two_fifth_last, .three_fifth_last, .four_fifth_last, .one_sixth_last, .five_sixth_last { float: left; clear: right; }
	.full-width { clear: both; }

	.responsive-box { position: relative; margin-bottom: 1.4em; clear:none }
	.responsive-box p img {  margin-bottom: 1.4em; }
	.full-width.responsive-box img { width: 100%; }
	img[class*="align"], img[class*="wp-image-"] { height: auto; }
	img.size-full { max-width: 100%; width: auto; }

}