rpi
sec:
http://www.pivpn.io/
https://pi-hole.net/
cam:
https://github.com/ccrisan/motioneyeos
https://kerberos.io/
Audio-Jukebox
https://volumio.org/
http://www.runeaudio.com/
http://www.raspyfi.com/
http://www.pimusicbox.com/
media center
http://openelec.tv/
https://osmc.tv/
http://www.xbian.org/
http://www.geexbox.org/
http://www.rasplex.com/
retroconsole
https://retropie.org.uk/
https://www.recalbox.com/
nas
https://sourceforge.net/projects/openmediavault/files/Raspberry Pi images/
pirate radio
https://makezine.com/projects/raspberry-pirate-radio/
kids os:
http://developers.kano.me/downloads/