Penny's OS 2.0 (S 14)

or NachOS or NanoBSD
or Nano-RK or Nanos
or Nasgaïa or NASLite
or Nature's Linux or Navyn OS
or NCOS or NCR Unix 

or NDIS or NDK 

or NECUX or Nemesis 

or NeoGEN or NeOS 

or Neopwn or NepaLinux 

or NetBSD or NetMAX DeskTOP 

or Netrunner or NetSecL 

or Netstation or Net/2 

or NetWare or Netwosix
or Neutrino or Newark
or Newcastle Connection or Newcastle Recursive VM
or NewDeal or NEWDOS
or NewOS or NEWS-OS
or Newton OS or Nexenta OS
or NeXTSTEP or Nexus
or NIDOS or Niigata Linux
or NimbleX or NimbusOS
or Nitix or Node OS
or Nokia OS or NoMad Linux
or NonStop or NonStop Kernel

or NonStop UX or Nonux

or NordisKnoppix or NOS
or NOS/BE or NOS/VE
or Nova or Novell DOS
or Novell NetWare or NOWSMART 386-OS
or NS/GDOS or NSK
or NSMOS or NST
or NSW or nSystem
or nubuntu or NUCLEUS
or Nucleus OSEK or Nucleus PLUS
or Nuclinux or NuttX RTOS

or NuxOne