ZenPhoto

A collection of various third party tutorials:

• This tutorial is already from 2006 but still applicable:
  http://www.ruzee.com/blog/2006/06/integrating-zenphoto-into-wordpress
• Einar Regilsson also provided some premade files based on the tutorial above here: http://tech.einaregilsson.com/2007/08/06/integrating-zenphoto-into-wordpress/
• A Zenphoto theme tutorial with the Wordpress navigation:
  http://www.natenewz.com/2009/10/13/integrating-zenphoto-and-wordpress/
• http://www.sparkhunt.co.uk/2009/11/a-basic-wordpress-and-zenphoto-integration/
• http://www.sparkhunt.co.uk/2009/11/404-errors-when-integrating-zenphoto-with-wordpress/
• http://www.strangerpixel.com/2007/06/integrating-zenphoto-with-wordpress-on-iis/
• http://www.rektproductions.com/adding-a-zenphoto-gallery-to-your-wordpress/

Take also a look at Zenphoto as a “plugin” (not working with current Wordpress versions anymore)