Just a WAG, but maybe metafilter.com?
Sweet! Do we get nifty hats?
I’d probably switch over to Opalcat’s Fabulous Forums of Fathom.
Zack Mayo: *Don’t you do it! Don’t! You… I got nowhere else to gooooo! *
Darwin Awards Board
For a while there, I thought the nearest parallel to the Straight Dope Message Boards, mutatis mutandem, was the Snopes Message Boards. I know at least a few Dopers go there. I used to and might again someday. NFBSK
Something Awful, the board I run, and probably Unaboard. Like interface2x, I’d probably attempt to create a new SDMB.
I would probably just stop message boarding and lurk on a few Computer technical ones. I have never seen another board as eclectic as this one and haven’t posted on a message board before SDMB. IIRC had board me years ago.
Something Awful and Snopes for me too. And the SDMB survivor’s board, wherever that might pop up.
I would spend a lot more time on 4chan. Of course, the exposure to that would make me even more loony and perverted, but oh well.