Why not take the second most popular forum you have and close it!?!
I rarely read "The Sandbox", so I wouldn't personally miss it. And we can do without all those irreverent Sandboxonians cluttering up the threads. If The Sandbox continues, these people might actually see a post that makes them log-in and participate in SL, and we certainly don't need that!
And the arguements that most online endeavors would give thier eye-teeth to have a vibrant discussion group, or that such space could be used to sell ad-space shouldn't be considered at all.
What's that? You already are closing The Sandbox? Well, egg on my face!
What a bunch of Johnny-on-the-spots you are!