Introducing Flexifilter
Today, the initial version of Flexifilter for Drupal 6.x was released. "What is this flexifilter?" you might ask. And the answer: Flexifilter is an awesome new module that's going to totally revolutionize the way filters are done in Drupal. It's going to become (almost) as important as CCK and Views for a site builder. Flexifilter was initially created by Corsix as a part of GHOP 2007-08.
What it is
Flexifilter allows you to define custom filters entirely through the user interface. You name a filter, you can create it. A filter to append a "back to top" link if the text is longer than 1000 characters? No problem. A filter to change links in the form of [[link|title]] into links in the form of <a href="link">title<a>? Downright easy. And, if you ever want to change the format from [[link|title]] to {{link:title}}, there will be no delving into php code necessary: just change your settings on the admin page.