If you’ve got about 40 of the same keyboard lying around (aww, I only have 37!) then might I suggest fashioning them all into a chair of some type? That’s what designer Dante Bonuccelli did with his “Text-ile” chair for the 2009 UMUL (Use More, Use Less) workshop in Milan, Italy.
It looks cool, yes, but is it comfortable? That all depends on the type of keyboard you use, I guess. Find yourself a bunch of super springy keyboards and maybe you’ve developed the next memory foam trend. That, or it just feels like sitting on a bunch of little plastic squares and rectangles.
This is just a concept for now but if it ever becomes a real product, it’ll probably be prohibitively expensive unless there’s a kids version that uses netbook keyboards.