There are a lot of companies already doing this: Shapeways, Ponoko, Stratasys direct, 3dhubs, proto labs, etc. Most have a 2-5 day turnaround but you can pay to

There are a lot of companies already doing this: Shapeways, Ponoko, Stratasys direct, 3dhubs, proto labs, etc. Most have a 2-5 day turnaround but you can pay to expedite and get parts next day. I have two 3D printers in-house at my job (Projet 460 and 3500HD) which we use for day-to-day prototyping and we commonly go to outside companies for limited production runs.