Take your icon game to the next level. Check out Fonticons, from the maker of Font Awesome.
             

fa-check-square · Unicode: f14a · Created: v3.1 · Categories: Web Application Icons, Form Control Icons

After you get up and running, you can place Font Awesome icons just about anywhere with the <i> tag:

fa-check-square
<i class="fa fa-check-square"></i>

Looking for more? Check out the examples.