This is interesting, which i had not heard about before. Notice how they are using both sides of a coil 
New Electric Motor is 50% Smaller but has 2x More Torque (!) : TreeHugger
White Paper on the motor's design:
http://kron1.eng.ox.ac.uk/media/pape...aper_2007a.pdf

New Electric Motor is 50% Smaller but has 2x More Torque (!) : TreeHugger
White Paper on the motor's design:
http://kron1.eng.ox.ac.uk/media/pape...aper_2007a.pdf