Open Mic nights for musicians - where to go?

I run a small open mic type event at Blackstrap BBQ in Winthrop, every other Tuesday, but I'm curious if anyone else on here has had success running a similar thing. I know Democracy Brewing in Maverick has a thing going on. Our band wants to expand to other open mic situations. Just trying to figure out how to get a bigger crowd or more importantly bigger roster of performers for it. Would love to hear anyone else's experience running or joining one of these sorts of jams.