Short and sweet:
In Nikola my static site/blog generator, the Tag pages used to just be a big list of titles linking to the posts in the tag. Now they can (optionally) look just like the blog does, but filtered. Check it out.
Minor tweaks still needed (like, mentioning the tag somewhere in the title), but the basic functionality (filtering, pagination, layout, etc) is complete.
To enable it in your site, just use master from git and enable
TAG_PAGES_ARE_INDEXES = True in your conf.py.