I was unfamiliar with a script for it, but, that doesn't derail this as a suggestion. Clickables is an example of an idea for everyone that was initially available as a script.
I'm unsure what real benefit showing clan next to user name has, but I can't see it as harmful, either.
Maybe a good way to do it is to have a block that the user could fill in (a pulldown with his available groups) that way, a member who is in a social clan that's important to him or her can have that show in lieu of a warring clan. This would limit the need to "enforce" and eliminate programming problems that could occur when a clan was a war clan and is now a social group (such as Eternal Empire).