Ancestry's Easter offer is for free access to 1901 and 1911 censuses for the UK until one minute before midnight on 1st April.
As well as England, Scotland and Wales this includes Isle of Man and Channel Islands censuses.
There's no access to the images for Scottish censuses, but images are available for the others.
Search 1901 and 1911 censuses now.
(My thanks to Marjorie Gavin for the tip-off.)