Roll on Monday?
"April Fools' Day is old enough to fox the anthropologists. Some see its origins in the pointless coming and going of Christ - Annas, Caiaphas, Pilate, Herod - shortly before Easter. Some say it commemorates Noah's first, fruitless attempt to find land by sending a dove over water. Others that it derives from the Roman feast of the Cerealia, which celebrated Ceres's futile search for Proserpine, abducted by Pluto. But fools' days exist in India, China, Japan and were probably endemic in Britain before it had heard of Christ or seen the Romans..."
"...The practical joke became quite fashionable during the period. For instance, the fourth Earl of Sandwich, Government Minister and Hellfire Clubman, used to amuse friends and neighbours with blasphemous services for dogs and pigs in his chapel, and appointed a baboon for his chaplain. Once he asked a distinguished cleric to dinner and asked the animal to say Grace, upon which his visitor cut in, "My lord, I intended performing that office myself, not knowing you had so close a relative in holy orders?" There's no record that the incident did, in fact, occur on April 1. But what certainly took place on All Fools' Day, 1698 was a joke that was repeated, with even more success, in 1856. A card, bearing an official looking seal made by a sixpence, went out to a large number of people summoning them to the Tower of London: "admit the bearer and friend to view the annual ceremony of the washing of the white lions." Both years the gates of the Tower were jammed with dupes..."
http://www.guardian.co.uk/theguardian/2013/mar/29/archive-1966-april-fools-day-ages
Who can forget good old San Seriffe?