Use Filtered Discussion Forums
A filtered discussion forum is a discussion forum whose entries you can filter according to assigned attributes. Attributes (or Filters) are keywords defined by your forum manager that are available for users to apply to entries. Attributes may also be registered usernames.
Forum lists attributes by category, and makes them available to users through hyperlinked titles, HTML selection boxes and drop-down lists. An example of a filter category is Entry status. Examples of states that you can apply to this filter category are: All, Open, Closed, Waiting for information, and Unassigned.
You can change the attribute state that you wish to use to filter the entries by clicking on the appropriate button in the Filters row. Forum displays a drop-down list of the available values you can use to filter through this category. Click on the value you wish to use.
All other features in the filtered discussion forum are identical to those of a standard discussion forum.
Attributes differ from standard discussion filters in that your filters are personal and appear on the page only for you; attributes can be seen, used, and applied by all users in the discussion forum.