OpenSyringePump
See full project description at hackaday.io: http://hackaday.io/project/1838
'3D files' contains OpenSCAD and STL files for customizing and printing the plastic pieces.
'syringePump' contains the Arduino code.
It requires the AccelStepper library, which you can find in the 'libraries' dir. Copy it into your Arduino\libraries directory to use. You can also get the library from the author's page here: http://www.airspayce.com/mikem/arduino/AccelStepper/