BUT! I've discovered that I can order a grande americano (espresso and water) with room (for me to add milk) and two pumps of my syrup of choice and holy crap, it's nearly half the price of an iced latte! On top of only paying about half price for my mock iced latte, it's strong, so I never leave feeling like I'm drinking coffee-flavored milk.
I imagine you could do this with iced coffee instead of an americano, but Starbucks doesn't have decaf iced coffee, so that's why I go the americano route. I'm only guessing, but I'm sure an iced coffee with room and syrup would probably be even less expensive.
If you already knew this and are thinking about what a waste of time it was to read this post, then, uhm, why didn't you tell me this trick!? It makes me wonder how much money I've wasted on lattes over the years, but then that makes me actually try not to think of how much money I've wasted on lattes over the years.