Categorize stories in 2 dimensions to identify boring ones Source:
Wayne D. Grant
Draw a big square and divide it into 2 columns. Label them 'Interesting' and 'Dull'. Let the team write down everything they did last iteration on stickies and put it into the appropriate column. Have them add a rough estimate of how long it took on each of their own stickies. Now add a horizontal line so that your square has 4 quadrants. Label the top row 'Short' (took hours) and the bottom row 'Long' (took days). Rearrange the stickies in each column. The long and dull stories are now nicely grouped to 'attack' in subsequent phases.
Hand out pens and sticky notes. Ask everyone for ideas on how to turn the next iteration / release into a certain desaster - one idea per note. When everyone's finished writing, hang up all stickies and walk through them. Identify and discuss themes. In the next phase turn these negative actions into their opposite.
Let team members appreciate each other and end positively Source:
Agile Retrospectives who took it from 'The Satir Model: Family Therapy and Beyond'
Start by giving a sincere appreciation of one of the participants. It can be anything they contributed: help to the team or you, a solved problem, ...Then invite others and wait for someone to work up the nerve. Close, when no one has talked for a minute.