Daddy called it Matrimonial Vine. Can be invasive but can also coexist with other stuff and climbs a fence like nobody's business. Some birds seem to like the berries, which will turn red as the plant matures.
It is Atropa belladonna or Deadly Nightshade. Its an very poisonous plant.
There have been many uses over the centuries, from using it to dialate the pupils of eyes to a witches flying ointment. It has psychoactive properties and the last link will gve you more information on this.
I don't think this is Atropa belladonna---the flowers of atropa are bell-shaped, and your pic shows petals reflexed into a star shape. What color do your fruit turn? I believe you have Solanum dulcamara, called bittersweet by some. If it is the Solanum, the fruits will turn yellow as they ripen. It is in the same family as the atropa, but not nearly as poisonious.