Not a burger and a salad, a burger salad. From time-to-time in a pinch, I'll get one of Carl's Junior Low Carb Six Dollar Burgers, without the cheese or catsup. Not a bad option and only about 5 grams of carb.
Of course, you can do your own lettuce wrap burger, or, you can just make it a salad (click for the hi-res image).
Very simple. Lettuce of your choice, lay on a heaping tbsp of mayo (important, otherwise to dry), then your burger (this had shrooms, garlic, yellow onion and pine nuts in it) on the mayo, garnish with onion, tomato (these were delicious heirlooms), dill pickle (if you haven't run out), and mustard & catsup (Trader Joe's: some sugar, but no HFCS and no unpronounceable ingredients).