I really have my doubts about a ribbon that long if it's a "pure" ribbon only suspended at the ends. I suppose a planar magnetic (ala' BG) would be possible in that length; however, it still will have the problems that Jim noted.A few months back I was sent a prototype of a pure ribbon that was about 24" long. While it sounded pretty good mechanically it was quite floppy. The weight from the magnet structure was about 40 lbs. and it pulled the reversible bit right out of my screwdriver! Not too practical for stacking them to form an array.