Anything spiny on the plant? Reminds me of Smilax.

I don't see anything spiny. It looks pretty basic - stem w/ leaves in opposite arrangement & vines. Small adventitious roots at the nodes, nothing else exceptional.

Most likely Common Carrion Flower (Smilax herbacea). It lacks prickles.

That does look really similar, but all the literature says the leaves of Smilax are alternate; these are opposite. I'll have to snip a sample tomorrow & see if I can get a better picture.

Errr, umm.. Yeah, I looked again & the leaves ARE alternate, not opposite. So I'm going accept the diagnosis of Smilax herbacea. And I'll put down the crack-pipe. :-)

Thanks for your help!

That is an invasive plant called air potato vine. I don't know the scientific name. I don't know about your zone, but it is quite a nuisance on the Gulf coast.