This is the Chipophone, an instrument created by Linus Åkesson. The instrument is basically a synthesizer inside an old electronic organ from the 1970’s and it makes it possible to play chiptunes, or “video game music”, on a physical instrument.
All signals from the keyboard, switches and buttons goes through a microcontroller that converts them to a MIDI-signal. That signal is sent to the synthesizer, which happens to be another microcontroller. The microcontrollers used in the Chipophone are the ATmega88.
In the video, the inventor himself goes through all the different settings possible, and he also shows his musical skills.
You can read much more about the Chipophone and how it works on Linus Åkesson’s webpage, http://linusakesson.net/chipophone/index.php
Malin Mattsson, Group P