Yes, they really do exist - lol. And since I'm currently on a diet...hard for someone who loves food, but I need to drop a few pounds that have crept up on me...I'm posting a super easy and very tasty recipe.
Take a box of chocolate cake mix, mix with one can of dark diet soda (Diet Coke, etc.), and pour into muffin cups. Bake according to directions on the box. That's it...a box of cake mix and a diet drink. You can do the same thing with yellow or white cake mix and diet Sprite or 7-Up.
Honestly, I didn't believe the person who told me about these, until she made some and brought them for me. These cupcakes are so moist and so good (and I beleive they're only 1 point in Weight Watchers). If you want, you can top them with light whip cream, and you've got a yummy, low-cal way to satisfy your sweet tooth.