A lend-lease M4A2 Sherman was dug up from the ocean after being sunk by a German U-Boat in World War II. The tank was meant for the Soviet army to be used on the Eastern Front and bound for Kola, Russia.
Apparently the Sherman has survived 70 years of saltiness fairly well because of the rigurous packing methods the Allies applied when shipping equipment. In total over 4,000 Shermans were handed over to the Soviets in WWII.
It is not known what the plans are for this tank (e.g. restoration)