This is a video roundup of currently available or prototyped 3D printers, a gadget which has been sitting on the sidelines for a while, but hasn't become mainstream yet. 3D printing machines are fairly simple in their operation, building any 3D shape, no matter how complex, as a series of contour slices which are hardened as a printer head slides back and forth across. But the results look like magic, real objects, in color, with moving parts, direct from a CAD model. The main reason that 3D printers, still remain a professional niche product, used by design firms rather than end consumers, is that their output is small and slow. In addition, more people know how to create text files for 2D printers than a CAD design, and this is unlikely to change in the near future. As a result of this small market, some of the marketing videos of 3D printers shown here look distinctly old fashioned for such a futuristic product. We long for the day when we will be able to print a full sized chair in ten minutes.

Cutaway drawings are a standard way of revealing the inner complexity of machines, and they are an art form unto themselves. Occasionally cutaways are real, however, as with this collection of cars which have been literally sliced apart to show their innards.

Creating the illusion that a staircase is floating in mid air has become a recent design trend. It can be achieved using a glass balustrade and hidden bolts, hanging the treads from above, cantilevering the stairs from a concealed beam or by using the structure of a spiral shape to make the entire staircase self supporting. Here are some of our favorites.

Trainspotting declared the worst toilet in Scotland, something which presumably takes some beating. Here are some of the worst toilets, kitchens, living rooms and bedrooms.