Obscure tracker is a tool designed for Nootropic's Hackvision.
It's a one-bit 16-steps monophonic music tracker.
It was created during the 2013 Databit.me festival in Arles.
Here is how it sounds.
And here is how it sounds through an analog filter and with a drum machine.

Here is the source code.
github
You'll need this version of the tvout library
(it could work in a very buggy way on more recent versions).
Here is a document about how to use it.