The HMS Rawalpindi has just been sunk by a German battleship - exactly 72 years ago today.
How do we know? And why do we care?
We know because a 24 year old history grad Alwyn Collinson has embarked on a six year project to Livetweet the entire second world war.
And we care because this is the most creative use of Twitter we've heard of in a long time. Emerse yourself @RealTimeWWII.