Whoa, National Margarita Day falls on a Saturday this year. This Saturday. Two days from now. You know what that means: We have very good reason to enjoy Austin's favorite alcoholic beverage this weekend. Especially since we have ample bars and restaurants in town to choose from that offer sterling examples of the tequila drink. Here's where to go for National Margarita Day festivities in Austin. Anthem, 91 Rainey St. All about tiki cocktails most of the time, Anthem adds Asian flair to Tex-Mex dishes, so it holds that this Rainey Street restaurant would have the EXSW Margarita, too...