Type
Tool
Creator
Dave Gray | Gamestorming
In a nutshell
This helps the group evaluate any ideas they may have gotten out of the brainstorming phase. It traditionally uses the variables: Easy to implement to impossible to implement, and normal ideas to original ideas to start to cluster. After the plotting on the matrix I would hold a voting activity for the group to then vote on their top 3 ideas with something like dot voting. Just so you can prioritize.