Tags and larger categories in Stack Overflow?
95873
Add "tag categories"
18647
Commenting out large sections
93826
How can I include custom post types on a tag page?
105353
Addition of themes for Stack Overflow
31750
How to allow certain html tags?
4740
Can we get a better view of newly created tags?
23805
jQuery autocomplete tagging plug-in like StackOverflow's input tags?
122211
Long answers on stackoverflow
90883
Tags on badge question list
132715
Create a tag homepage/FAQ
21182
Is it okay to add id/class to  tag?
66156
Stack Overflow interesting questions implementation
135791
Should I prevent search engines indexing tag/category pages?
41265
Ability to sort/reorder interesting/ignored tags in sidebar
82357
Is support for Markdown tables on Stack Overflow planned?
77231
Span Stack Exchange sites for tags, searches, and related questions
51519
The Efficacy Of Stack Overflow's Question Title Filter