Lokomotiv (Software Synthesizer) (2014)
Free virtual-analog synthesizer with VST and AU support.
Programmer (C++)
http://www.kvraudio.com/product/lokomotiv-by-archetype-instruments

iBartender (2013)
Hardware + iOS software that teaches you how to make cocktails with a liquid level sensor.
Arduino Programmer

BuildSet_Win (2012)
A tool to fetch and compile internal source code
Programmer (C#)


*Click pictures for details.