Granny Pop out of Bed

It's a type of bind weed, the scourge of gardeners.  But some of the common names for this plant are fun:  Old man's nightcap, Bride's gown, Wedlock, White witches hat, Belle of the ball,  Devil's guts, and Granny pop out of bed, along with less interesting ones like Hedge bindweed. 

(See here)