Way back in November 2006, I blogged about this stranded oil rig on the island of Tristan Da Cunha and the dangers it could pose for the ecosystem of the island.
I finally remembered to go back and see if anything had been done and the rig was towed into deep water and sunk in February, 2007.
A colony of Brazilian Porgy fish had apparently made their home around the rig and had swum with it to Tristan. It was hoped that the fish would follow the rig to where it was sunk and be eaten by predators.
You can read the whole saga here