I'm using the built-in Path module to change Drupal Page links from a format like "/node/1234" to "/about-us". The latter link format is easier to read and is SEO friendly.
At the top of every page is the primary navigation. Currently when viewing the /about-us page the primary navigation links are displayed as follows:
Home | About Us | Contact Us
Notice that the /about-us page is linking to itself (self-linking). Instead, the primary navigation on the about-us page should look like this:
Home | About Us | Contact Us
Is it possible for Drupal to detect which Page is loaded and then refrain from displaying a link to the current page? A Page should never link to itself.
You will probably have to get into some custom theme/module development to make this happen unless you can find a third-party module to do this for you (I don't know of any, I'm afraid). I can recommend VanDyk's "Pro Drupal Development" for getting started in that whole world. Then poke around in /includes/menu.inc to get an idea of how the menus are constructed and what theme functions you can override.
Alternately, if Javascript-disabled people aren't too much concern for you, you could always write some quick jQuery (or whatever your preferred tool is) to remove the link from the currently viewed page.