Derek Sivers spent two years trying to make Rails do something it wasn't meant to do, then realized his old abandoned language (PHP) would do just fine if approached with my new Rails-gained wisdom.
Alternative Ruby implementations seem to be growing in the Ruby community. JRuby is most advanced now. Charles Nutter and Thomas Enebo, two main JRuby programmers, comment. O’Reilly Media.
This O'Reilly Network article has two parts: the first is an overview of P3P, written by Simson Garfinkle; the second section, written by Lorrie Cranor, offers a more in depth look and examples.
Lorrie Cranor, author of Web Privacy with P3P offers an introduction to P3P and an overview of what you need to do to prevent IE6 from blocking your cookies.