It might not seem all that great from the simple example provided, but Compass (http://compass-style.org/ http://compass-style.org/, uses SASS) is a great examp

It might not seem all that great from the simple example provided, but Compass (http://compass-style.org/ http://compass-style.org/, uses SASS) is a great example of how mixins can make your life so much easier. For example, if you want to make an inline list it's as easy as: li +inline-list