I am trying a new and unusual tomato this year, Indigo Rose. Indigo Rose has a striking purple coloration on its skin. The purple color come from anthocyanins. It was bred at Oregon State University by researchers in an attempt to make tomatoes with more antioxidants. A tomato named OSU Blue has been circulation in tomato circles for a while now. Indigo Rose is the strain, variety, selection, etc... of OSU Blue that the researchers decided to release to the public.
So far it has been very productive although it is a smaller type tomato so this is not a great achievement. It's very pretty and the the purple color shows more in areas that are exposed to the sun. I'm waiting to see what they look like when they ripen.