This snippet is more than 5 years old and may no longer be best practise, test before use.

Font smoothing

-webkit-font-smoothing: antialiased; is the webkit feature that smooths out custom fonts keeping them tidy and clean, you can also use subpixel-antialiased as an alternative to antialiased.

Although until recently webkit was the only CSS feature to allow this firefox have released their own version and this comes in as -moz-osx-font-smoothing: grayscale; as of Firefox 25