Below is a link to a 5+meg video of my 65 at idle:
2011-07-14_19-36-49_93.mp4 video by mkoebra95 - Photobucket
I think the driver's side exhaust manifold to h-pipe donut gasket has blown out. I bought one and will be replacing the old one in the near future. Car sounds mean, but leaving it leaking exhaust will lead to problems.
I haven't crawled under the car as of yet, so for all I know, there's a hole in the H-pipe. Either way, I'll need the gasket.