In the past we've talked about Ikea's Elderberry Syrup, but if you're looking for something a little less commercial, P&H Soda Co. offers classes (if you're in NYC) on soda and syrup making or you can order their products online.
We love our Soda Stream more than almost any other kitchen appliance and use it daily and we're pretty sure these would make a nice addition to your pantry. Do you make soda syrup at home? What flavor would you like to test out? Let us know in the comments below!