CellStruder is a 20mL syringe extruder powered by a NEMA stepper motor, capable of of precise liquid extrusion at the microliter level. Originally developed in Jeff Tabor's lab at Rice University, this device is currently being used for cell printing, enabling research in synthetic biology, biological pattern formation and engineering of cellular logic. An example print of E. coli cells expressing green fluorescent protein is shown above as well as microscopy of printed cells.
http://www.thingiverse.com/thing:109040 by Ravi Sheth
Cellstruder v2 is released, now with retractable syringe mechanism: