The Tagline Machine can help put your branding direction into words. Here are a few examples of the Machine in action. For a great example of TM web copy, go here.
The Tagline Machine is built from over ten years of of tagline and copy development in Hollywood. Its style is smart, witty, but accessible.
For a few inside secrets on TM's approach to slogans check out this very useful blogpost by, umm, The Tagline Machine's very own Simon Gornick.