So my friends were knocking me for this last night, but I think they are excellent. Especially after I tried a tequila sunrise, which is just disgusting. Way too sweet.
I was surprised no one had ever heard of doing this because I always have — try putting a little beer in your margarita.
Unless you are a huge fan of tequila, beer is the perfect solution to the bite that a margarita will give you. It makes the drink less sweet - and can even fix a crappy one.
Most bartenders don't mind making you a full margarita, and then if you ask them to top it off with a little beer it works great. Definitely get a light beer, though. Anything dark or micro brewed would probably cause clashing flavors.