Allow a project to be associated with more than one category

Since many gadgets and reports can be based on project categories, it would be helpful to be able to allow a project to be associated with more than one category.
For example, we have projects that we categorize as Products. We would like to also categorize as subset of those projects as Capitalized or as Outsourced.

This would allow us to use the many gadgets and reporting available based on that category since it is the project that is a category - not individual issues that could be labeled within that category.