By specifying a value for the LINKTO parameter you can enable the user to create hyper links to an arbitrary URL - much like the ability to link to normal Composite documents.
The URL can be freely selected - this can be a fully qualified URL (i.e. "http://www.microsoft.com/net") or a partial URL to a local resource on the site (i.e. "showProduct?product_id=84832").
By combining a advanced render plugin, a friendly URL and the LINKTO attribute you can enable the user to create datacentric links, i.e. creating a link to a specific product presentation or the like.
Example:
<DATA TYPE="Ex" UNIQUEID="123" LINKTO="/addToShoppingBasket?product_id=123" />