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Rum cocktails have a reputation of being on the sweet side and having a tropical connotation to them. There are some very good sweet rum drinks but one of my favorite is the Hemingway Special.
Sweet and Strong
Mai Tai *
Daiquiri * (try the non-frozen variety)
Bahama Mama *
A Day At The Beach *
Blue Hawaiian *
Sweet and Weak
Pina Colada *
Tart and Strong
Tart and Weak
Balanced and Weak
Cuba Libre (Rum and Coke with Lime) *
Balanced and Strong
Long Island Iced Tea *
* these drinks are the more popular and you will probably have an easier time finding them in most bars.
See Webtender or Dale DeGroff's Site for recipes.