Os'es have been built. You don't need to spend time in that. You'll find one as small as a few hundred kbs to as big as 10s of gbs. For all kind of architecture

Os'es have been built. You don't need to spend time in that. You'll find one as small as a few hundred kbs to as big as 10s of gbs. For all kind of architectures and all opnsource. However you need to find a way to install the os on compatible device. This is no easy task and will require you to flash ROM. For every device....... Or find a device that supports booting from an sd card. I don't think there is any phone out there that supports that. There are not even that many laptops that can boot from an sd card slot. But they can from an sd to usb adapter... >novel ways of communication- Put everything on wifi relays, or communication with other peripherals HIGH FIVE!!!!! This is a very good idea. But then again how will GIPO attached devices send wifi signals and understand incoming wifi signals? You'll need a separate chip for that (If I understand correctly) that would have radios and antennas. I'm sure you can find a cheap way to build such a device using electronic components that you can find online. A wifi enabled usb is very very cheap. wifi usb cards would be even cheaper, I think. A mobile phone like this is a complete package for about $10-$15.