I'll be adding to this list as I get sample sites published. They will mostly be in PHP with MySQL, but the same concepts apply to sites in any language and database combination. Unfortunately, most of my work is for internal use, so I cannot provide links to them.

Live Sites:

These sites are LIVE so be nice as you test features.

PaymentBrowser.com
Our new development project is an application that runs either as a web browser for web based applications or along side Windows applications and adds PCI/PADDS compliant credit card processing to any application.

OneHealthSystem.com and OneDentalSystem.com
These sites provide secure payment solutions for the Medical and Dental professions.

iRobot.com
We implemented many features in the iRobot customer support site.

Cabaret Restaurant
This restaurant site is completely database driven allowing the customer to edit content and change menus.  

More to come...