The builtin Iguana Tools repository contains example channels that demonstrate modules containing various useful tools we have developed over the years. This includes things like: date parsing, filtering for duplicate messages, retrying intermittent errors (like a lost database connection), send a rich HTML email with attachments, etc.
Simply import the channels that you are interested in, review the comments in the code, and read the corresponding article in this section of the documentation.
You can also view the repository on GitHub: https://github.com/interfaceware/iguana-tools.
Be sure to come back and review this section as we will continue to add examples when new modules are developed.