I've got 72 square feet of blue periwinkle, it is pretty easy to just pull up by hand then lay cardboard over it to keep the shoots from coming up.
Uses:
-Locally it goes for $7 for a small potted start; I
should probably just
sell it.
-When it is big and mature makes great cordage, you could try and weave some rope or baskets.
-Medicinally it can be used to remedy mensural bleeding (internal/external astringent), sore throat (gargle it) and diarrhea (ingest it...I guess).
As for permanently getting rid of it I have no idea.