http://www.househacker.com/ househacker/tags/sofa BonBon Trading might be just what you're looking for. The clever design allows the sofa to 'effortlessly' convert to a bunk bed. From the site:

Doc XL a convertible sofa-bunk bed solution with rotating mechanism. Doc is a comfortable divan with slipcovers, which requires a simple gesture and no physical strain to become a practical bunk bed with a safe ladder that is both a support element and a protective barrier. To use the item only as a bed, it is sufficient to remove the back cushions. The item can be converted from bed to furniture piece without having to remove the sheets and blankets, thus offering the possibility to always dispose of a ready to use bed.]]> http://www.househacker.com/permanent/Space-Saving-Sofa-Converts-to-Bunk-Bed eco-furniture.com. It's great to see so many green products that don't look fringe or 'hempy' hitting the marketplace. The more normal environmentally friendly products appear to consumers, the more market penetration they will achieve. It can only help matters that such striking choices like these exist for today's consumer.

]]> http://www.househacker.com/permanent/Gorgeous-Environmentally-Friendly-Furniture