This is a collection of parts for a single RepRap 3mm extruder (much like a motorised glue gun), printed out on three of the smallest sheets Ponoko do. It is recommended that they be printed on 3mm, 4.5mm and 8mm acrylic. Transparent acrylic lets you see what you're doing and looks quite good!
Assembly instructions and parts needed shown here: http://reprap.org/bin/view/Main/PonokoExtruderAssembly
See vik@diamondage,.co.nz for RepRapper's discount details.