I'm having a Blue Christmas, you can have one too 

'Blue Christmas'

2 - 3 Tbsp Blueberry Ginger Syrup
1.5 cups unflavoured sparkling water

In glass measuring cup, stir sparkling water, syrup, and 
lemon juice with cocktail spoon; pour into chilled glass.


Blueberry Ginger Syrup

1 cup fresh or frozen blueberries
1 Tbsp grated ginger
1 cup granulated sugar
2 tsp lemon juice

In saucepan, combine above ingredients. Bring to boil,
stirring until sugar has dissolved. Reduce heat to 
medium, mash blueberries with fork and simmer for 5 to
7 minutes. Remove from heat; let cool for 30 minutes.
Strain syrup through sieve placed over bowl. Refrigerate
for at least two hours before serving. Can be covered and
refrigerated for up to one week.