Who knows what plant this really is - it has strange purple flowers, makes balls full of seeds & grows in vine

Could be a passion flower, or in the south, a common weed, called May-Pop. It is a Vine.

Who knows what plant this really is - it has strange purple flowers, makes balls full of seeds %26amp; grows in vine
Sounds like a clematis to me.
Reply:I think what you are describing is a Clematis. They are a beautiful vining flower. I hope this helps.
Reply:Is it perchance, an Angel's Trumpet? I have grown Angel's Trumpet's in my Garden and they are a muted purple. The flowers are only in bloom for about a day, but they are big. Much bigger than a standard flower, almost like a huge petunia. After they have bloomed they produce a spiny pod that contains seeds.

http://www.boloji.com/photoessays/flower...

Or there is a plant that produces purple flowers that look like loose pompoms and they are called Monarda. They are a wild flower and related to Bergamot. They produce pods but only on top of where the flower is.

http://www.fsperennials.co.uk/catalogue/...

There is also the Shoo Fly Plant, it too produces purple flowers with white in the middle. It is a hearty self seeder and considered a weed.

http://www.oardc.ohio-state.edu/weedwork...

Then there is the clematis, it is a climbing plant, a vine. It produces pods of seeds.