One script which generates live Linux ISO image with minimal effort. Based on the first published version of Minimal Linux Live: http://github.com/ivandavidov/minimal
You should get familiar with the Raspberry Pi boot specification and build MLS in a way that the Pi bootloader runs your kernel and your initramfs. Currently, there is no roadmap to support Raspberry Pi devices.
How I can boot this OS with Raspberry Pi 1 / 32 bit ARM CPU? Using SD Card Reader built in?