The Bayou Corne Sinkhole was formed near Baton Rouge Louisiana last September, likely as a result of the failure of salt caverns below. This video shows a stand of trees being swallowed by the sinkhole in pretty dramatic fashion.
A colleague of mine (thanks Jamie!) sent me an email with this intriguing title. I have no idea where it originated, but it is an interesting compilation of some amazing photos and short descriptions of various natural and man-made "holes". A few sinkholes, glory holes, and of course open pit mines. By the way I didn’t write (or edit) this, just some minor formatting updates. Check it out.