The Dry Soda Company produces a line of great sodas that have delicate, simple flavors and that are not sweet. I think of them as sodas for grown-ups.
I served the Dry Lavender Soda at the Old Colony Club's annual Past Presidents Night Gala, and it made a great cooler with the summery Barr Hill Gin.
I have some of the Dry Juniper Soda in the fridge now, still thinking what to do with it. Of course, they are delicious on their own, but I cannot resist the creative impulse when I find a new ingredient to play with!
I buy these at Nature's Greengrocer in Peterborough, NH, but they must be available in other places.