Crossfire Injection Vault has an "Active Topics" listing on the home page. It gives you the current list of everything that everyone's talking about in the past 2 days. That might be a nice feature.
I don't mind a membership fee but others might... it would have to voluntary like on CF.
Personally, I would gladly pay $100/year if it keeps the trash and BS out....
What about a separate section only accessible to 'supporting members', like a off topic garage talk section ??