What is process.memory giving ?

I'm not sure I understand. The Module class exists to handle node-style require commands (and to allow the Web IDE to dynamically load modules), and it is not a way to page in/page out data unless your program is specifically designed for it.

Of course you could always just execute files directly with: eval(require('fs').readFile('foo.js')

Espruino was also designed with the possibility of automatically storing less-used data in slower memory - for instance the SD card. That would make it massively flexible - however it is yet to be implemented as for the uses that Espruino was designed for, 48kB of RAM actually goes a long way.