Here's what Cook's Thesaurus has to say:
mirin = sweet rice wine = sweet sake Pronunciation: MEE-reen Notes: This is a very sweet Japanese rice wine that's used to flavor rice and sauces. It's not usually consumed as a beverage. Aji mirin is salted, so adjust the recipe accordingly. Substitutes: 1 tablespoon dry sherry + ½ teaspoon sugar OR sherry OR heat two parts sake and one part sugar OR white wine + sugar to taste OR white wine
Deja Moo: The feeling that you've heard all the bull before.