As we predicted in July, Shapeways 3D print service now offers Sterling Silver as a build material for 3D prints. At this point it's only an experiment until November 7th, apparently for the tall foreheads at Shapeways to determine if it really works.
Interestingly, the Sterling Silver is not actually 3D printed. Instead, they print your design in wax and then use it in the ancient lost-wax casting technique to mold the desired silver item. If you like they can even polish the item after casting to bring it to full silver luster for an extra USD$15 per item. Obviously, printing in sterling silver is more complex and time consuming than just a straight 3D plastic print - leading to their USD$48 per cubic cm materials price. But it's Silver!
Be aware there are some design rules in effect for using silver, including minimum wall thicknesses and detail. However, these restrictions should not prevent you from printing out your very own set of Gold, Silver and Bronze Olympic Medals!