Marion Dorsett

The WordPress Database Table Optimizer plugin will automatically make sure that your WordPress MySQL database tables are always optimized.
I’ve also included an admin page located at Manage > Optimize Database. This page will allow you to confirm your WordPress MySQL database tables are optimized, show you the number of rows per table, and the size of the table.
<h3>Arbitrary section</h3>
This plugin uses Aidan Lister size_readable PHP function to show the file sizes of the MySQL tables. I’ve changed the name of the function to avoid naming conflicts with other plugins that may be using this function as well.
http://aidanlister.com/repos/v/function.size_readable.php
Special thanks to David Potter (http://dpotter.net/Technical/) for catching my oversight.
http://www.figmentthinking.com/wordpress-database-table-optimizer/#comment-74

Figment Thinking WordPress Database Table Optimizer

The WordPress Database Table Optimizer plugin will automatically make sure that your WordPress MySQL database…

MD Geus

Simple tool you can use to backup your WordPress tables and give an optimize and analyze command.
Functionality: 
* Optimize tables 
* Analyze tables 
* database backup
! make sure you test the import of the created backup file, before you rely on the backups !
<h3>Known issues</h3>
Currently there are no known issues

DBtools

Wordpress plugin for DB maintenance and backup

Figment Thinking WordPress Database Table Optimizer vs DBtools