Here are a couple Tableau apps from Interworks. Two of their developers created these in their spare time and they don't charge for these.
- Color tool: Use this to change the color theme of your workbook
- Drawing tool: This one is my favorite. You can draw shapes over a map to create your custom regions (ie. Walmart Regions)
When you explore the rest of their site, powertoolsfortableau.com, you'll see they offer other tools for sales such as a workbook merge, performance analyzer and best-practice analyzer.
We used Interworks for our advanced Tableau training and would recommend their services.