Wysiwyg

The WYSIWYG module combined is my favorite for rich text editing in Drupal 6 and Drupal 7. Here's how I set it up.

Better Formats

The best part about this module is that each role can have a default text format.

Drupal 7 core allows for reordering the formats in the UI, thus picking a default too. However, there is no role based ordering, as there is with the Better Formats module.

Devel

Essential module for developers. Should be disabled in production environments.