WordPress › Word Filter Plus « WordPress Plugins

Update or clean the contents of your site, by filtering or replacing words and phrases in your posts, pages, excerpts, titles and comments.

The Options page which controls which mode (Off/Active/Passive) under which the plugin will operate.
The Replacement screen with some examples of use.
The Replacement screen with the inline help displayed
The Batch screen which allows you to update all existing content on your site at once. This screen lets you configure, start and cancel batch operations.
The Import/Export screen which allows you to upload a CSV file, or save the existing replacement data to your computer.