Okay, this is kind of a silly idea, but I got it in my head, and I think it could be pretty cool: A VST plugin that can run inside the DAW, and that is a (as close as possible to) fully-functional Tux Paint program. It could be really cool to even expand Tux Paint to have audio input/output functionality.
I have basically no idea how this would work under the hood. But let's find out.