1) searching for stories by keywords via HN Search,
2) scanning the main page and the new page with word search on the page (implemented as CTRL-F in many browsers),
3) searching for best comments on the bestcomments
http://news.ycombinator.com/bestcomments
page,
4) searching for active threads on the active
http://news.ycombinator.com/active
page,
5) searching for comments by users with high karma averages on their comments by following links from the leaders
http://news.ycombinator.com/leaders
page, and
6) doing site-restricted searches of the site with Google
https://www.google.com/search?sourceid=chrome&ie=UTF-8...
to focus on comments with particular keywords? I use all of those methods on different occasions to find good content here. What could we all do with tags (implemented how?) that we could not do by those means?