We hit up the following breweries while we were down in Nashville.
Yazoo Brewing Company
Turtle Anarchy Brewing Company
Cool Springs Brewery
Blackstone Brewing Company
Yazoo was hands down our favorite brewery, and had our favorite beer, a smoked porter named Sue. This place is a definite must-visit for anyone that's visiting or passing through Nashville.
Turtle Anarchy was a brewery I definitely want to go back to. They had some really nice offerings, including 5 different versions of their porter (standard, w/ chiles, w/ peanut butter, w/ coconut, and on nitro). All but the chiles were very, very good. They're also in the process of greatly expanding and will be canning some of their offerings by 2015.
Cool Springs was the most hit-or-miss brewery we visited. The Mango IPA was fantastic, and their Tripel and Quad were both very good, too. But they had this Mt. Dew ESB that was supposed to taste like Mt. Dew. It was completely awful. It tasted like someone pissed in Mt. Dew that had sat out in 110 degree heat for a month. To their credit, this was a "special" brew that was done by a winner of some contest. They don't ever plan to do it agian.
Blackstone Brewing Company was just your average run-of-the-mill restaurant/brewery combination. Nothing special there.