FriendlyCase is a WordPress plugin by kelter and sauldraws that enables Friendly, Word Capitalization in Post Titles.
Users can automatically format their post and page titles to properly capitalize each word in the title and follows a series of rules to exclude short words etc.
Current words excluded from First Letter capitalization are: A, An, And, At, For, In, Of, On, Or, The, To, With
For example, both the function and filter would reformat:
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG to:
The Quick Brown Fox Jumps Over the Lazy Dog