Open a Preferences.tps file to add, clone, edit, remove, and re-order your Tableau colour palettes. If you're a real palette hoarder, you can select palettes for export into a new .tps file.
Create a new Tableau colour palette from scratch, either by magically extracting colours from an image or picking them yourself. You can also import the XML of an existing palette to update, add, remove and re-order colours, or change the palette type.
Of course you will need to enable JavaScript to experience this joy.