If you like margaritas served in a glass with salt, rub the outside rims of six glasses with a cut lime and dip each glass lightly into a plate of kosher salt.
Combine the lime juice, lemon juice, Triple Sec, and ice in a blender and puree until completely blended. Add the tequila and puree for 2 seconds more. Serve over ice.
If you prefer frozen margaritas, halve each of the ingredients, double the ice, and blend in two batches. Serve with a cut lime.