We have created a site with multiple applications (youtube clone, phpBB forum, Zen Cart, Almond Classified and coppermine photo gallery and a turnkey recipe script).
Each application has its own database and this is a new site so there are no current users in any of the databases.
All of these applications are loaded and working but we need a single sign on for paid and free memberships, preferably through the shopping cart.
We would like a login form in the header of each page and an option to view and change user information or forgotten password in the footer of each [url removed, login to view] already logged in, the login form needs to be replaced with a personalized welcome.
Most of the site requires a free registration but some areas require an upgraded (paid) membership such as uploading images and videos, and other areas of our site.
We also need a script that will update a form in the header of each page everytime something is purchased in the shopping cart with 10% of the purchase price. For example if the user purchases a video for $[url removed, login to view] the amount in the form would go up $2.00.