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.
I stumbled across this video for the geotechnical engineering centrifuge at Rensselaer Polytechnic Institute. Centrifuge testing is a popular way to economically test models at much higher loads and pressures than you would normally be able to in the laboratory. The goal is to more accurately represent the real world conditions. Click through for the video.