Casady & Greene has released a grammar checking app for Mac OS X called Grammarian X. Grammarian X is a grammar checking app designed for use in the educational and professional fields, and is compatible with several popular programs. According to Casady & Greene:
Grammarian X, the premier grammar checker by Casady & Greene, is released and available as an electronic download! Grammarian X is a Mac OS X native application that takes full advantage of the great features of Mac OS X, and supports Carbon and Cocoa applications.
Grammarian X is a universal grammar checker which works with virtually every program on your computer, whether or not a program has its own grammar checker. Grammarian can even check grammar in such Mac OS X applications as: TextEdit, Mail, Tex-Edit Plus, AppleWorks, NotePad Deluxe, BBEdit, Eudora and FileMaker Pro.
Grammarian X addresses the needs of our education base, K-12 and higher ed., by adding the ability to lock and unlock the Writing Rules feature. This greatly empowers teachers in a classroom setting. Parents and teachers can set and lock the Writing Rules settings for Phrase Usage, Grammar Mechanics, Punctuation and Writing Style.
You can find more information about Grammarian X at the Casady & Greene Web site. Grammarian X is available for US$49.95.