What's the best way to approach this sort of system?

[Jade Elizabeth]

So I run a non profit for creative people called Creative Burrow. Right now we have boards for different types of works (such as poetry, stories, drawings, music, etc) and we're using icons to further define works.

The problem with this is it's somewhat nonspecific. In the design board I am posting fliers, website designs, posters, and all sorts of things and they're all using similar icons. I enjoy how deviantart does their categories but that's not really viable with a forum system and I do not want a tonne of boards/cats. So I want to look into something similar so I can filter things from the message index and perhaps even the unread templates... but I wonder what the best way to go about this is?

Some ways I have come up with are:
1. Message icons (current system, not very great needs another layer)
2. Post prefixes
3. Some sort of "tag" system
4. Adding a field to ask "what type of art/writing/music is this" sort of thing

If I can add another layer then my "wanted poster" in the design section which uses the "crime" icon can be further defined as a "poster". My website design for a petshop using the "internet" icon can use the "pets" icon instead and be defined as a "website design".

[JBlaze]

Tagging is usually the best way to go about something like this. This mod can do that for you quite easily.