The Monome Grid was the hottest DIY electronic music controller. It was so hot, multinational corporations built their own versions marketed toward users of production platforms like Ableton Live. Akai did this circa 2009 with the APC40 controller, which has an Ableton logo imprinted on the enclosure. They don't have a high resale value and are marked "legacy" by Akai Professional. Considering the Ableton Push product is released, this unit doesn't have much relevance anymore for Ableton but it's an interesting general purpose grid controller.
My local hackerspace, Noisebridge had one of these donated. I'm not particularly interested in Ableton as a music platform, which made this unit seem unremarkable. I was so wrong!
The full midi spec, including sysex is available online. The Monome grid OSC spec is published online. It is possible to send sysex data to the unit to put it into Ableton mode (the good mode) without running Ableton. This mode decoupled the button LEDs from the key presses.
So I set out to build a drop-in replacement for serialosc. Here's a video showing what I got after a week.
The code is online and is cross platform, running on macOS, Linux and Windows. It requires a Python 3 environment, so it's not yet "packaged".
There's an interesting forum thread on Lines with some discussion on the topic.