Variable Fields for Use in KB Articles

There are so many articles that I would love to template across the KBs of different clients, but I end up having to copy and edit them. If we could have custom fields for each client that contained only text (for now), then insert those fields into KB articles - I could essentially template an article and place it inside multiple clients' KB to have it customized for them. This would be really beneficial. And it gives me the ability to make a change in one place and have it update in all linked locations.