Lower calorie sweeteners

Options
I am at work, so I don't have a lot of time to search if someone else has started a topic about low-calorie sweeteners. I drink at least one cup of coffee each morning, but I need a little something sweet in it. When I saw how many empty calories are in regular sugar, I was shocked. I switched to Splenda. When I tracked it yesterday, the first one I used said there are no calories on it. The one I used today says there are 4 per packet. Not bad, so I know I could stick with it and it wouldn't throw me off my calories too much. I was just wondering if there is a sweetener that is lower in calories.

On topic of sweeteners, but off topic of original post: Are sweeteners even healthy for you?