It's Go!  It's an incredibly long-running thread!  It's.. it's.. exactly the sort of thing you'd expect bored arc-t regs to do!

Here's the basic idea -- a thread is started with a regular sort of post, plus an empty go board.  Interested parties can respond to the post, but only if they also play a move on the go board (taking white O or black #, depending on whose turn it is).

If you respond to a post without playing a move, it is assumed that you resign the game. And if you lose the game, then clearly you lose the argument, as well.  : )

A couple neat things could happen: if several people respond to the same post, the game will branch out in all sorts of directions.  Or maybe someone will post a message/move and not post again until two levels deeper in the thread, so that they effectively change colors.  Or maybe everybody will get sick of the go postings and kick me out of arc-t.  We'll see.

The Go board in the posts looks like this:

The # marks are the black stones, O marks are the white stones.  The last move played is surrounded with > < to make it easier to find.

One of the best introductions to the rules of the game on the web is at http://www.cs.umanitoba.ca/~bate/BIG/BIG.contents.html.
Pretty much any other go-related link you could ever need can be found at http://nngs.cosmic.org/hmkw/golinks.html.
You can also play online at Yahoo! or at the No Name Go Server.  You can play at Yahoo without any extra software, as long as your web browser supports Java, but you need to download a client program to use NNGS.