The Geo Tags redirection script enables you to easily create cross-platform Nfc Geo Tags: touch one of those with your phone, and the maps application will show the user the location! For more information, check out the information page. You can get the source code of the script (under BSD license) from the Nokia Developer Projects page.
To write a Geo Tag that uses the script, just add the “Geo” record in the Nfc Interactor tag composer interface, and select the “Generic redirect nfcinteractor.com”. Note the licensing and availability restrictions of the hosted service!