Korg announced that they had a Development board for the Korg Prologue - which features a digital oscillator and effects chip. Korg recently announced that they would offer an SDK for the Prologue's digital aspects and this boafd allows you to code for the digital oscillator and the effects and test without having to own a Prologue.
Its not for sale, just available for interested developers who might want to expand that aspect of the Prologues features.
Its pretty serious stuff, you have 32k of memory to write your oscillator code in C so you might need to know what you are doing.
But in June the firmware update for the Prologue allows for the opening up of that part of the features - kind of extending the recent Korg hackable approach - remember those labeled points on the PCB for the volcas and 'tron products?