Oh running Linux on a MCU without MMU.

I feel there is a gap between MCU and modern CPU, and also between the software running on top of them. The missing piece is a mid-size computer with: - A processor, single or multi-core, with computing power like 20 years ago, but modern fabrication process. Maybe without MMU for simplicity. - RAM between 100MB~1GB and DDR2/3 bandwidth. - An OS designed and implemented for this type of hardware rather than tailored Linux.

I don't think you can use it for working or your daily entertainment, so I guess not a good business to attract interests.