I'd like to say, on another web site, please ask a question on AskUbuntu tagged
foo, and make that a link to the 'ask' form here with the tags already populated, so that it's more likely the right people will see it quickly. Is there any way to make such a URL?
Well who knew? There is!
You can also suggest the initial title with
title=something (join the two with an
Example from developer.ubuntu.com (See the ask a question link):