FogBugz has a ton of built-in categorization options, but if you need an ad hoc way to group cases and wiki articles together, use tags. Tags are lightweight in that you don’t need to pre-configure anything (e.g. set up a new custom field) but you can still search and set up filters based on tags.
Adding tags to cases and wiki articles
To add tags to cases, edit a case and add tags view the Tags field on the left side of the case. Existing tags will auto-complete as you type.
To add tags to wiki articles:
Viewing tagged cases
View tagged cases by creating a filter or view a search for tag:tag-name. Via the “Refiner Further” option in the filter menu:
Via a search for tag:tag-name: