A blockers visualisation board
Hack day at the office. Don't judge the quality of the code(just a few hours to do something valuable).
As an addon to face to face communication when we face a blocker, publishing and visualizing the blockers since the first moment they appear until the moment they are unblocked, could help raise the awareness and increase the feeling for shared responsibility that Agile avocates for.
Also knowing how long a blocker toke exactly to unblock and also the average block time of the department could be an interesting and detail to encourage collaboration throwards blocked time reduction and therefore faster feedback.
Feedback is the most important part in agile the quickest are up internal feedback loops the more efficient we will be.