Adds a global setting to turn the wpautop filter on and off. It also allows you to override this default for any post by adding a wpautop custom field
Beautifully simple plugin.
Has allowed me to fix validation errors caused by WordPress putting in <p> marks in places that clashed with divs created by plugins.
This little plug-in does the trick, but it's also not as user-intuitive as it could be. That being said, it's still very simple and easy to use once you know what you need to do.