Ícones de diversas extensões dentro da pasta images/ico/[extensão].gif A coleção de ícones está em: https://www.dropbox.com/sh/wpvzxn8zvgxa8lc/zc06b0rQ0T

icones

[class^="icn-"] {
  display: inline-block;
	height:18px;
	width:18px;

	float: left;
	margin-right: 5px;
	background: url("/images/ico/default.icon.gif") center center no-repeat;

}

$ext : (ai, avi, bmp, cs, dll, doc, docx, exe, fla, gif, htm, html, jpg, js, mdb, mp3, pdf, pps, ppt, pptx, swf, swt, txt, xls, xlsx, xml, zip);

@each $i in $ext {
	.icn-#{$i} {
		background-image: url("/images/ico/#{$i}.gif");
	}
}