The Caipirinha is Brazil's most famous cocktail, rivaling the pisco sour as South America's best combination of lime juice and locally produced spirits. Caipirinhas are made with cachaša, Brazil's famous distilled sugarcane rum. Pisco sours are made, of course, with pisco, a brandy distilled from grape wine.
There are some great variations on the classic caipirinha. Try some of these recipes from Colleen Graham, About.com's guide to cocktails:
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I might be getting carried away with taking polls, but I'd be interested to see what happens with this one... If you were sitting on a beautiful South American beach at sunset with your favorite friends, and the waiter from the beachside bar was waiting expectantly for your complimentary cocktail order, which would it be - the caipirinha or the pisco sour?