I've used all kinds of fish sauce over the years but I think Three Crabs is my new favorite.  It has a nice fish flavor yet isn't overpoweringly salty like some brands.  That's a plus when you want to add soy sauce to your Asian food in addition to the fish sauce.  The ingredients are water, anchovies, hydrolyzed wheat protein (secret name for MSG) and sugar.  I wish it didn't contain MSG, so I'm giving it 4 stars instead of 5.