OpenDrop is a ~$800 microfluidics platform from GaudiLabs. It can be used to programmatically move droplets of liquid around a matrix. When I saw the video, I thought it was an LCD display, but it's real liquid being moved around.
Potential applications are lab on a chip devices for automating processes of digital biology. However the present design should also open the technology to other field and allow experimentation to find new applications. Including the field of art, music, games and education.