I'm writing this retrospectively, as I've already done some work on this project.
I've been taking a lot of interest in the Gigatron project since I saw a video about it on YouTube, and then watched the Hacker Hotel video explaining its fascinating architecture - I don't own one yet, but I'm hoping to have some money after Christmas!
On the Gigatron forum a user posted about porting Forth to the Gigatron. I've also been interested in Forth, and stack-based language runtimes for a while, but haven't quite had the impetus to write one myself. The original post asked if people were interested, and questioned whether the vCPU, or v6502 was the better choice for implementing it, whilst leaning towards the v6502. I replied that I thought that the native 8-bit Gigatron instruction set would make for the cooler hack. Marcel and monsonite (the original poster) both thought that this was too hard. But I couldn't stop thinking about it... so here I am, setting out to write a ROM based native Forth for the Gigatron.
Who knows if this will result in any useful code, but I already feel like I've learned a few things.
The next update will be on what I've got so far, and my general approach.