Your database can be automatically saved and archived every hour and/or every day, and backups can be emailed to the address you specify. You can also restore the data to your WP DB or an external DB, which makes copying your database to another server and easy task.
Updated March-13th

EZ Backup

Keep your database safe with scheduled backups. Multiple option for off-site backups also available.

michitzky

On a page within the “Tools” Submenu, you’ll find a simple form which lets you choose the ingredients of a current Backup:
<ul>
<li>Uploads (either by scanning your Upload Directory, or by fetching Attachments from your Database)</li>
<li>Active Theme (and its parent theme, if used)</li>
<li>SQL-Dump containing the Mysql Database</li>
<li>A list of active Plugins</li>
</ul>
Backups will be stored within a folder in wp-content and be downloadable from the Backend. Once the downloads are finished, the backup files on the Server can be flushed.
What’s good:
<ul>
<li>Simple: Choose what is included in your Backup and download the resulting ZIP Archive from your Backend</li>
<li>Unobtrusive: It’s nested within the “Tools” submenu and comes without any bling bling, following default WP Backend Styles</li>
<li>Lightweight: 28KB zipped, 72KB unzipped</li>
</ul>
The plugin author does not take any responsibility for the safety of your data or the integrity of the generated backups.
Credits:
This plugin uses 2createStudio’s shuttle export Script for SQL Export: 
https://github.com/2createStudio/shuttle-export
Banner-Image on Repository: B. Walker, 11.08.2010: http://www.fotocommunity.de/pc/pc/display/22021026
Icons: FamFamFam Silk Icons: http://www.famfamfam.com/lab/icons/silk/

mk Simple Backups

It just does what is says. Quite light and easy to work with.
Thank you.



Nice plugin

Allows you to create simple backups on a dedicated page nested in the "Tools" Menu.

EZ Backup vs mk Simple Backups