Homemade Ginger Ale

When I was in Lisbon last month, we went to a sushi restaurant for dinner one night and I was intrigued by the ginger cocktail on the drinks list. I asked our server what was in the cocktail and he said the star ingredient was their homemade ginger ale, which he divulged was just house made ginger syrup with soda water. It was so potent, in the best way possible, it made me want to try to make my own at home.
Ingredients [yields 6 to 8 drinks]:
4 oz. fresh ginger root
1½ cups sugar
2 cups water
+ seltzer water
+ lime

Start by grating about half the ginger and adding it to a pot with sugar and water. Pop the pot onto a burner and heat over low until the sugar has completely dissolved.
Take the syrup off the hob and grate in the rest of the ginger. Allow the syrup to cool completely before sieving to remove the ginger bits.
Pour the syrup into an airtight container and chill.
To make the ginger ale, pour 2 to 3 ounces of syrup into the bottom of a glass. Top off with 6 to 8 ounces of seltzer and squeeze in some lime. Serve immediately.
This is one of the most refreshing drinks ever. It's spicy and fragrant and delicious and I can't go back to regular commercial ginger ale. There's barely any ginger taste in that stuff. But this stuff? It's glorious.
Here's the recipe page: