Frosted Ultra Detail is the material of choice for people 3D Printing very small things at Shapeways with the ability to 3D Print o.3mm walls and details down to 0.1mm but we do see other materials used too. Take a look at just a few of the thousands of 3D Printed miniatures in the Shapeways gallery....
Formula 1 Miniatures - 2011
Autocannon arms v0.5
1:144 US M24 Chaffee Light Tank V3 (Set of 4)
1:144 WWII German Landwasserschlepper I (Set of 3)