I'm now fairly certain Meyer lemons were put on this Earth to serve this purpose and this purpose only: the greatest margaritas ever. The addition of rosemary adds the perfect hint of herbal woodiness that marries so well with the tequila and Meyer lemon.
1 cup Meyer lemon juice (from about 9 or 10 small Meyer lemons)
1 cup tequila blanco
1/2 cup Patron Orange or other orange liqueur
2 sprigs fresh rosemary, cut in half
Combine lemon juice, tequila, and orange liqueur in a small pitcher, or a shaker if you're feeling fancy. Stir or shake to combine.
Pour into 4 glasses over ice, and garnish each with a sprig of fresh rosemary.
If you wanted to get super-funky with this one, you could try infusing the tequila with the rosemary overnight. That would for sure up the ante with the herbal-flavor.
Recipe by 20something cupcakes at http://www.20somethingcupcakes.com/2012/02/meyer-lemon-rosemary-margaritas/