Sorry if this was posted already.
"A Rhode Island 3d printing meetup has been experimenting with printing dissolvable support structures on consumer grade 3d printers. They found that a material called High Impact Polystyrene (HIPS) can be dissolved in a chemical bath of Limonene, while leaving the ABS material intact. […]
Ball and socket joints, complex caged gear mechanisms, many previously extremely difficult to print models become much easier with this process. The extra bonus – the Limonene solvent leaves the finished model smelling like oranges."