Mr. Tenuki
As of January 2009, "Mr. Tenuki" is an SDK [1] player.
In case you're wondering... no, "Tenuki" is obviously not his real last name. (For that matter, although he is indeed of East Asian descent, he is not even Japanese.)
If you're looking for this user, we're sorry to tell you that it's not possible to reach him right now, because he has just played an off-server tenuki. Please come back later for updates on his status.
[1] On KGS, that is. The exact rank cannot be listed as he hasn't played Go much since late 2007.