Around these parts, Texas Star and Grapevine can put up a fight with any muni you can think of IMO.
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Texas Star is awesome. Played it two years ago, really nice course.
Around there parts in WI, Washington County is pretty nice. It is ranked pretty high usually among the top muni courses in the nation. It has become a once a year course for me usually.
Laurel Hills in Lorton, VA is very nice. They are hosting the U.S. Public links this week.
Here's a link to some photos - http://www.usga.org/ChampEventPhotoGallery.aspx?id=21474852555&aid=21474854187#21474854028