"Multi-Diggs"

I know this is a thing on Reddit and not sure of its adoption, but I use it heavily. In the near future, I would love the ability to group multiple communities into groups based on the subject matter. For example, one group being "Tech", one being "Art", and another being "news". Each of these will house a handful of communities and based on the type of mode I am in I can go into one of these groups and explore that general topic. Id like to see if this would be something others would use?