A brainstorming session should involve a competition to see who can provoke the most contributions from other people. Today’s invention is a way to recognise (and possibly reward) individuals who contribute in this way most effectively.
Everyone who attends a brainstorm would be encouraged to scribble on a shared smartboard (one at a time).
As they write up a new idea and shout it out, they also link their new idea to the one which provoked it (if any did).
The board recognises who said what by the different pens in use and can immediately calculate, and display, who has made the biggest number of fertile suggestions.
Extra points could be awarded to nth-order ideas, ie those which ’caused’ n other suggestions in parallel. The highest kudos would be for ideas which sparked off a chain of m subsequent ideas. So perhaps the metric for idea quality = n*m^2 ?