Automatic tag suggestions
46020
Automatically determine tags while writing a question
48768
Is there some markup to post tags?
122614
RSS feed of your favorite tags
107858
Request to be able to delete tag synonyms
90883
Tags on badge question list
68981
Improve the usability/intuitiveness of direct comment links
71649
Ability to add tag to Interesting/Ignored by clicking on it
109571
Multiple tags for 'Favorite tags'
77231
Span Stack Exchange sites for tags, searches, and related questions
134574
Wrapping long tag names in question list
125808
Could the tags autocomplete widget please show more than six options?
107498
Answering tag questions
69062
Please add a tag search functionality to Careers
62870
Tab for questions that are labeled with favorite tags
140992
Automatic labeling of enumeration items
125928
How does Stack Overflow suggest related tags?
89797
Add a selection of default tags to all metas