Ideation is the creative process of generating, developing, and communicating new ideas, where an idea is understood as a basic element of thought that can be either visual, concrete, or abstract. It is about particpants posting ideas, voting on them and watch ideas through a custom lifecycle as they come to life.

Obviously, that's one of the things you can do using a Q&A site:

• The idea is "published" in the format of a Question.
• The Answers to it are about making those ideas come to life, e.g. via answers such as:
  • Steps involved to transform the idea in a viable product or service (planning).
  • Rewards granted to the author of the idea (reflected somehow via some type of reputation system).

Read more about it via these articles:

• Ideation in the Workplace.
• Use Collaboration and Ideation to Drive Innovation.