This sounds like a good blue cocktail....

The Blue Bayou
Ingredients:

1 cup of ice
1 1/2 oz vodka
1/2 oz blue curaçao
1/2 cup fresh or canned pineapple
2 oz grapefruit juice
chunk of pineapple for garnish
Preparation:

Pour the ingredients into a blender.
Blend until smooth.
Pour into a chilled margarita glass.
Garnish with the pineapple.

Anyone?