A toolbar that lets you adjust Typekit font previews.
Typekit Tweaker lets you adjust font previews on Typekit. Adjust size, line height, letter spacing and colors, all from a sleek & simple toolbar. You can also insert sample text with one click.
Typekit Tweaker also remembers your font settings & text, so as you browse fonts you can compare with all the same settings without additional work,
More info is available at http://kylefox.ca/typekit-tweaker/