Calypso has several locations in Nashville. I have visited them all.
You really can't beat the beans and three for a vegan gluten free value meal. The black beans are good (ask for no sour cream), the sweet potatoes are a little mushy but good, the callo (greens) are fantastic, and the wild rice mix is filling.
The best thing about this place is you can go here with anyone - non-vegetarians, kids - there are good options for everyone. I used to really enjoy the spicy roasted jerk chicken myself.