Add FontAwesome icon with only CSS

I wanted to add a check mark provided by the FontAwesome project to a bunch of <li> items, but without mucking around in the HTML. Here’s how I did it:

li::before {
  font: 20px FontAwesome;
  content: "\f058";
}

Because FontAwesome is just a specialized font (think Wingdings 2.0), it’s easy to plug it into the content property. Coupled with the ::before psuedo-selector, and it’s a piece of cake.