Give an incentive for finding duplicate questions
50607
Reward finding duplicate questions - +10, +2, -5
97874
Notify when my question has been linked from another question
7406
When merging questions, leave the duplicate one as a placeholder
117767
Put bounties on other people's questions?
32251
Search for "similar questions" across multiple sites?
31940
Add an alert when answering a question that has at least a close vote as duplicate
27856
Add the duplicate suggestion feature to mobile theme
7142
Showing meta questions in the same manner as linked and related questions
103901
How to build a 'related questions' engine?
145116
Better drafts feature for questions
70754
Encourage Questions to Include Code Samples
71476
How to deal with duplicate answers posted long after first answer(s)
22458
Add ability to flag answers as duplicates
39711
Link up the excellent search engine that gives "Questions that may already have an answer" with the search box
76517
Split reputation: one for questions and one for answers
25593
Encourage users to select 'Accepted Answer' for old Questions
83537
Add an answer to the question with many existing answers already