I am just curious . Apart to play games on the camera display, what benefits would have running Freedos or linux on camera?
Maybe more programmability for certain automated tasks, or more deeper control of the camera core? Don't know...
Recently I discovered Kolibri ,that's a very lightwight OS just 1.4 Mb , entirely compiled in c++, complete with GUId and it is very fast.
It requires only a few megabyte disk space and 8MB of RAM to run. Kolibri features a rich set of applications that include word processor, image viewer, graphical editor, web browser and well over 30 exciting games. Full FAT12/16/32 support is implemented, as well as read-only support for NTFS, ISO9660 and Ext2/3/4. Drivers are written for popular sound, network and graphics cards. http://kolibrios.org/en/index
Could be useful to know?