Five Guys is a chain restaurant serving burgers, hot dogs, fries, and shakes. It is quite expensive, but very good. There are a few locations scattered around Boston, in Allston, Fenway, and Downtown.
The fries are some of the best out there, and the servings are very generous. The burgers are also great, and toppings are free. I suggest getting the burger "all the way". It is quite expensive, so you would get the best value this way. I am not much of a shake person, but Five Guys shakes are amazing. I'm not really a hot dog person either but they're pretty good here. Peanuts are available for free, but you may need to ask for them. Soda refills are also free if you eat there.
Overall, Five Guys has incredible food (I have yet to find a better place for burgers and fries), but it may put a dent in your wallet (and some weight on your body) if you eat too much of it. 8/10.