A man dies and goes up to the Pearly Gates where St. Peter greets him.

St. Peter takes him into the reception room where the walls are covered with hundreds of clocks.

"What are all the clocks for" he asks.

"Ah" replies St. Peter, "those are lie clocks which only move if you tell an untruth"

The man is captivated and points to a large clock and asks "Who's is that one"

St. Peter replies "That is Mother Theresa's, and it's not moved one second in all the years it's been here. And next to it is Abraham Lincoln's which has only moved twice in over two hundred years"

The man continues to look around and remarks "It's nice and cool in here on a warm day" and St' Peter replies pointing to the ceiling "Ah that's Boris Johnson's clock on the ceiling, we use it as a cooling fan"