Rullo sofa bed, designed by Karim Rashid for Danish furniture manufacturer Softline was introduced at the Milan Furniture Fair 2011 . Rullo is a convertible sofa bed made from Softline’s modular concept. The mattress bends to form a low backrest and is held in place with a simple strap. The base slides apart to receive the mattress. A design that is functional and so simple it makes you think “Why did I not think of that?”