No, there is no software that actually writes to the VFD. Yet. I may come up with something for my personal use, and I'll let everyone know when. If any programmer wants to try something, let me know, I can forward communication specs for the display.

I was under the impression that Hugo has already got something working with some changes to the kernel. Perhaps he would like to share that code with the world. It could be incorporated into 3.0 or maybe into Hijack.

You don't need to send ascii letters only. You can do graphics at 115,200 BPS. Some math:

128 pixels by 32 pixels = 4096 pixels per screenful. Assuming the kernel code only sends 1-bit graphic information, that means you could theoretically (depending on how the VFD wants its graphics inputted) get about 28 frames per second. That's not bad. And it could become a full display extender at that point.