Am rubbish at links so can't show you one of these (maybe someone else could do the honours).
This is a new product from Tomy. It consists of a big sheet, plus two pens. The brilliant bit is that you fill the pens with water, and because the sheet is made of a special material, you can write and draw on it, then, as the water dries, the images fade and you can use it again and again and again. The sheet is edged with the alphabet and numbers 1-10, which magically appear when you scribble over them with the water pens. Me and ds2 (age 3) have so much fun with this, its the best £20 I have ever spent on a "toy".
Ds has tried scribbling on the door and floor with the pens, but as they only contain water, they can do no harm.