Just visited my local Wilkos and almost everything they have stocked for Christmas is 50% off marked price.
So cards, decorations (previously posted) but also chocolates, sweets, shortbread, gift sets. Even the elctricals such as hair dryers (that were part of the Christmas gift lines) were 50% off.
Presuming this isn't a local deal and is nationwide.
EDIT: Someone has edited the deal picture. This is not the Really Useful Sale. That is on but for things like toilet brushes! - Which were not part of the Christmas Stock.