Help, please: how to develop - and take forward - good ideas?

Yesterday's post was self indulgent and silly (not to mention giving 'OldAndrew' an open goal).  To have something different on my homepage, I am posting from my mini break in France.

I am looking for thoughts on a question which is at the front of my mind right now: what are the best conditions for small groups of people to develop good ideas and (the ' and' is very important) commit to taking the ideas forward.

A few suggestions to get us going:

1. A group incentive is good but it should not be so large that it distracts (see Dan Pink's world beating Animate) or introduces perverse incentives.

2. Apparently, according to some research I plan to look into properly next week, 12 is the optimum group size to develop ideas (strikes me as a bit big).

3. There needs to be clear norms - or even explicit rules - which stop the people with the loudest voices or strongest opinions from dominating.

4. Like the incentive, the focus should be medium sized - not so wide that the conversation lacks a thread, not so narrow to stifle imagination.

There's four to be going on with - over to you dear readers ...