In short, yes, something like that...
Some ideas I've brought to rick on the matter:
Paid Groups, you pay, you play... Basically you pay, you get added to specific product groups, these groups can be either private access, anti-ads, etc.
Donations through your forum - basicaly added to the above, only strictly in a donation matter.
I'll have to lookup my thread for others, i just woke up (5pm, oh yeah!)