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

fa-twitter-square · Unicode: f081 · Created: v1.0 · Categories: Brand Icons

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

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

Looking for more? Check out the examples.