Automatic children

Hi,

Been trying to find a way to use taxonomy to create "automatic" children.

Basically I am working on a site that will display content based on location. So there will be a taxonomy with this kind of structure:

• Country
  • Region
    • City

The tricky part though is that under every city I want to have the same terms, lets say services like Locksmith, Plumber, etc. I know I can go in and set multiple parents for a term, but since this site will end up with hundreds or thousands of cities it will be practically impossible to administrate it by manually add a new city parent every time a new city is added.

At the same time I want these services to only show up if there exist a matching content for it, i.e. a locksmith in that city, and also a counter so the term will say "locksmith (5)" if there are five locksmiths listed for that city. The services should also be listed in a block.

Also, I would prefer to have two vocabularities, one for location and one for services in this case.

I believe http://drupal.org/project/taxonomy_filter might help doing this, but it is only in dev for D6 and last snapshot is since July last year.