Thanks to the Zetica twitter feed for the heads up on this one.

This video shows the collapse of an iceberg arch in Antarctica.  It is beautifully filmed as well as being technically very interesting:

Particularly interesting here is the increasing event rate for material dropping from the arch before collapse (we see the same thing for rockfalls) and the way that the pillars performed after the arch collapsed.  Note also the development of the waves as the iceberg collapses and fragments.