For one cup of...
Vegetable curry: 250 calories
Fish curry: 300 calories
Chicken curry: 400 calories
Beef curry: 500 calories
Pork curry: 600 calories (assuming you leave all the big pieces of fat in)
Obviously, if you increase the amount of oil or coconut milk from what's called for in the recipe, that will increase the overall calorie count. So this is only a rough estimate; YMMV! But I find it really helpful, and thought others might as well.
Don't take this as a guide for restaurant curries -- they will generally be much more heavily loaded with calories than homemade.
Someday, I'll do carb counts too, but it may take me a while!