Building on Philip's success i could suggest We can revive an old hw design for external ram based storage...the rampac ... which plugs into the system bus. Easy to make. Works on m100 t102 t200.
Or A variant of quad could provide ram for both memory banks plus ram disk. M100 only. Lastly rather than switch ram from an m100 bank to a cpm bank one could copy away the m100 ram image to a holding spot in lower memory. That would allow only bank switching in the lower 32k. The upper 32k would always be the internal m100 ram. This is an improvement since it makes the memory handling simpler.
