Strange wild weed with berries like tiny watermelons

[JayPoc]

This is growing down by the foot of the drive. It has thorny stems, white flowers, and is making these cute little round berries that almost look like miniature watermelons. Any ideas?

[Mr_bobo_]

Ohh Ohh that weed !
Solanum nigrum. (maybe it is not nigrum, but it's Solanum and weed looks like)
Have flowers same as potato. Did he have something under ground? If not - weed.
Berries are poisonous!

[pinksand]

I agree, definitely looks like some type of nightshade.

[!potatoes!]

solanum carolinense, horsenettle.

[Luch]

Definitely solanum linnaeanum