E3D just released their Volcano super high flow nozzle upgrade that will speed up your 3d printing by pushing more filament trough the hot end.
Putting on a larger diameter nozzle and extruding more molten filament also improves strength since the more mass and more heat improve adhesion between the layers.
Volcano product home page:
Here is a video demonstration and presentation of Volcano:
Here is a picture of Volcano heater block and various diameter larger nozzles: