=== Other Operating Systems ===
==== QNX ====
QNX (and, more recently, Neutrino) is a commercially available microkernel.
It features a message passing kernel, and its architectural papers
influenced VSTa's author greatly.
==== Plan 9 ====
Plan 9 is an iteration of the OS design concepts first applied to design UNIX.
Its filesystem view of system services is also present in VSTa.
==== Patrick Bridges' OS Page ====
A large index and survey of operating systems.