The Ann Arbor Scrabble Club meets Wednesdays from 5-8pm at Arbor Brewing Company (meetup page).  All are welcome, no board needed.  The group has been meeting since at least 2006, as documented in this Observer article, though back then it met at the Firefly (now gone).  Regulars include Steve Lawrence, the de facto organizer and host, and Chuck Armstrong, one of the top players in Michigan.