ARM (Advance RISC Machines)

http://en.wikipedia.org/wiki/ARM_Holdings

NTP (Network Time Protocol)

http://www.ntp.org/ntpfaq/NTP-s-def.htm

An internet protocol used to sync computer clocks to some reference.

FUSE: Filesystem in Userspace

http://fuse.sourceforge.net/

Using FUSE it is possible to implement a fully functional filesystem in a userspace program.

Linux kernels 2.4.X and 2.6.X

Has an example using hello world program.  A fuse hello world is a couple of hundred lines.

 

Grid Security Infrastructure (GSI)

http://www.globus.org/security/overview.html

public key cryptography

asymetric cryptography