Some concepts for pens and pencils for a company I worked for.  Designed in Solidworks and Alias and rendered in Hypershot.  Physical prototypes were built using an FDM 3d printer and were primed and polished by model makers.  The pen on the top is inspired by a revolver where multiple tools (ink & gel pens, mechanical pencil, pen knife, small eraser)are arrayed in a cartridge while the action is a gas-spring dampened mechanism.  The bottom pen ('nunchaku') has a black and red pen, though only one is active at any given state.  The color of the pen is mapped to the actual appearance of the pen so when you fold away the black to red, the black pen recedes while the red pen extends.