Using Tags to separate Clients and User

I would like to see a use of tags in the client/user section. A work example: we've got a lot of freelance workers with specials skills and located in different regions. At this time we add these as users in the DB. But searching the right freelancer is a pain.
So it would be nice to add some specific tags by adding the users. An autosuggest field (ajax) may be useful to avoid duplicated tags.
The User list could contain a tagcloud or a searchfield for the quick access of the right freelancer.

Thanks.