During the June SeaTUG event, Zachary Mazzoncini from Decisive Data presented "Telling Your Data Story" where he outlined 10 practical tips for dashboarding. His presentation is attached and portfolio of workbooks can be found here: http://www.decisivedata.net/tableau/
We also highlighted a safe streets advocacy group named Seattle Greenways (Seattle Neighborhood Greenways :: Safe Streets for All ). They showed their Tableau Public dashboard https://public.tableau.com/profile/troyheerwagen#!/vizhome/TimetoCross/HowMuchTime that has been included in city grants to create safer intersections and crosswalks. Their viz tells a simple but powerful story, with some nice usage of filters/parameters for what if analysis for the user. This was based on sensor data they picked up using technology they demonstrated on site at SeaTUG.
The community really enjoyed both presentations!