A good friend and I co-founded a startup that invented 3D printers, double-decker bicycles, and other whimsical inventions for sale out of a garage.
One project included reverse-engineering the Printrbot to fix excess vibrations that plagued the early units' Z-axis carriage. However, even milled Aluminum stock wasn't enough - the founder eventually used wider gantry guides to mitigate the problem.
This iterative research led to knowledge of low-cost 3D printing method Fused Filament Fabrication (FFF). We eventually advised Purdue University's first forays into 3D printing on behalf of the Mechanical Engineering and Mechanical Engineering Technology departments.
Around campus, our upcycled bicycles elevated everyone we met.