I love lemongrass, have it growing in nearly every house I've lived in. I usually just use it in Thai recipes or added to some lemon for a nice drink when my throat is sore but If you don't like alcohol, move on by... but this recipe is really good!
Lemongrass Mojito Cocktail Ingredients
4 sprigs mint
15mL sugar syrup
45mL white rum
1/2 cup ice cubes
1 stick lemongrass
150mL soda water
Halve the lemongrass stick widthways, finely chop bottom half and muddle with mint and sugar syrup in cocktail shaker. Add rum and ice, shake vigorously, pour all into suitable glass, top with soda water. Using the back of the knife, crush cut end of remaining half of lemongrass and garnish drink with it, crushed end inside the glass.
Here is a link that might be useful: info on lemongrass