At the weekend I visited an old family friend who moved into my old family home after we had moved out. He said he had an envelope for me they'd found lodged in the chimney. Inside the envelope were two letters, one from my brother, aged ten at the time and the other from me, three years older. On the envelope was the date, 18th December 1996. The letters were addressed to whoever found them in the future. Mine had a little drawing of myself and questions for the finder. But my brother's is my favourite. I might hide the letter back in a chimney and hope robots come across it in a few thousand years..