Open Mics - Metro Detroit. If you know of any open mics in the area not listed below, please email the info to info @ TrinityHouse.org.

The Drowsy Parrot (Saline) - Thursdays hosted by DAVE BOUTETTE

Dragonmead (Warren) - Thursdays from 8-11, hosted by Christopher White

Boulder's (Plymouth) - Mondays 11 p.m.

The Ark in Ann - Wednesday night one once a month.
http://www.theark.org/

Xhedos in Ferndale has them fairly regularly.

Mama's Coffee House in Birmingham has one before their monthly shows. Reservations for two 15 minute slots (call/email to reserve) and will take one, maybe two walk-ins if those slots are filled.
http://www.mamascoffeehouse.org/

Dick O'Dows (Birmingham) Mondays - S.G. Wood hosts

Off-The-Wall Coffeehouse
http://www.off-the-wall.org/

Acoustic Coffeehouse
2610 West Jefferson
Old Downtown Trenton, MI
734-676-1468

Celtic Kettle Coffeehouse
http://www.celtickettlecoffeehouse.org/

Other venues have open mic nights as a special event (Live from the Living Room, Acoustic Avenue, Acoustic Avenue Coffee House, Full Circle) but not on a regular basis.